DAPPCON 2025: From Dapp to Super Dapp - Sebastian Burkhard

Transcript

[Applause] So good evening everybody. Last talk on this stage I think. Uh I'm from Yodel. I'm Sebastian the founder of Yodel. And we're basically building an Apple Pay but cardless. And what I'm going to talk about is sort of the journey that we went from just a simple DAP into a a super DAP. Now about the name Yodel. Uh the way we got to that name is we saw what's coming after hodling. We've been hodddling all our coins all the time. We're great little savers. Uh it's time to spend them. Yod some live a little. Spent that

token for something real. Uh so that's how yeah inspiration for my name. Yodelmeister is my handle. It's from the real Yodel masteri u straight from Japan redefined yodel languages chicken yodel and now the key question is what is a super app some people don't really know it kind of started back in the mobile payment uh times with in China with Alip pay and vchhat pay what they basically did they gave a container within their payment app and gave it to third party developers ers that they can fill up like a little iframe web view that they

can build the app and use the underlying payment system of Alipay. WeChat copied it. I don't know who copied both copied each other but basically a super app is an app that has a user base and a specific feature that you can use as a third party developer in Alip Pay Chinese people who can pay. We have now in the crypto space a lot of projects trying to be super deps such as Worldcoin. They basically bring I think like 10 million users who have their eyeballs scanned so you know that they're for real. Uh main usage these days is anti- civil protection I guess for people who want to drop a token.

You've got forecaster having a mini app framework and they basically have social media features and bring a lot of socially active people into the game. Now what we are trying to offer to the people is a user base that pays in real life. We are a payment dep uh to pay in real life in the shop for coffee in the supermarket also online for e-commerce stuff. Uh you can tap into this user base. can tap into communities such as network cities, meetups, side events who build upon our mini basease to adjust to give their people their customized super app experience in their community.

Uh so at the core it's payments in real life. So let's look at how that looks like. Uh we've got a video, you go into the shop, you use basically your phone where you have a wallet and with the click of a button on the action button or on shortcut, you open the Yodel Pay tab within the wallet. You pick a token to pay. You scan a QR code on the payment terminal. Uh you pay and within seconds the payment is done. Payment terminal updates. You're done. You can go. The merchant eventually will receive the money through fiat trails from the payment network that they have signed up. They not they do not have to do anything. It's a standard QR code that

shows up on the terminal anyway. Now that works on quite a few countries nationwide like Switzerland, Sweden, uh Asia have these QR codes. Brazil, Argentina, it's quite a common thing. We're tapping into this system and I show exactly how. So to summarize, you can now pay for anything with any token. Tether gold, chip up, pepe, trump coins, whatever you want with a token that you already have. Now once upon a time, Satoshi had a dream of peer-to-peer payments where your crypto is money and you sign with your private keys.

The status quo these days is you've got an Apple Pay wallet where you can load a credit card inside and then you can pay in the respective network of the credit card. All these card networks are multi-billion dollar mega companies who all uh sort of have the same sort of merchant acceptance network with about 100 million merchants. Now next you can already pay most people say with crypto credit cards. So let's just have a quick look at how these guys work for instance pay. You sign up your KYC you deposit a specific token on a specific chain. You tap your credit card

and then pay will pull the money out of your deposits and pay. It's not really peer-to-peer. I I'd argue is also not your keys and it's usually not a token that you actually want to hold, but it works fine. I'm not against it. It's nice. Now, the way we work, the old pay, it's different. We don't pull money out. We let the user push money to into the payment network. So, you go with your wallet, you scan a QR code, we resolve the QR code at the payment network that you have the contact with. We know how much to pay. We let the user choose the token he want to pay with. Typically, they just keep the default that they

usually pay. They sign with the wallet that they have. Onchain transaction goes live to to our Yodal Pay smart contract that swaps and pays the money into the token that the recipient wants. In this case, the recipient is a middleman. It's a so-called blue code issuer. They will receive a stable coin, pull it over the day and send it over into the payment network at night in a batch off-ramp and uh SEPA transfer process.

Now this payment network uh I've been I know it very well. I've been first engineer and CTO over eight years and they basically have become a payment aggregator. They aggregate lots of other payment networks that all the users can pay into including all the y users. So together we can reach a total uh merchant acceptance networks of about 160 million merchants but we keep aggregating. We keep adding more either through blue code or directly through a similar system. uh imagine Brazil pics and we also try to understand every crypto QR code or payment protocol. So when whenever you

want to pay you can do it with your Yodel Pay wallet. Now that's all cool but typically everybody has the same question on their head and that is can I tap and I say yes you will be able to tap the same way you can do with your Apple Pay wallet. will take a little bit longer, but it will work. Now, the reason I personally like the push flow very much is because it's very close to the cryptonative flow where you sign your transactions with your keys, you push the tokens towards another party and that will enable us to basically then come up with a peer-to-peer solution that is exactly similar for the end

user. We can go to a merchant and say, "Take this QR code." You save some money and you can have a bunch of extra fun features through something called mini apps. Uh the way it works for the end user, it's we distribute a tab. It's like a unis swap tab. It runs in your browser in the inapp browser of your wallet. With a tab, you don't need to have any downloads. You simply sign up once. you KYC with one of our providers to pay in these in their respective networks and once it's done you click scan QR code and pay done works with any DEP any wallet and so on

if you want to tap and pay we will provide a native app that's required but then you can basically load your credit card inside and also tap in all the other places that you can't use a QR code for instance Now this is usually the time that people have a lot of questions. If anybody has some burning questions, please go. Otherwise, I'll go into the flow how we started out uh developing that idea from the beginning.

When we started about two years ago, the basic problem we tried to solve was that I can't easily send €100 euros in USC to my parents or vice versa. Uh it's still not properly solved. Uh CRX addresses are annoying. ENS addresses back then and still are not consistently supported by the wallets. You could couldn't send on Polygon like that. So, it was a very shaky experience. We were never sure. You paid a lot of money for your ENS address, but it wasn't universally supported. The people who sent, they didn't know what USDC is, how or there's like so many versions of them. They didn't know which one you want, which chain and so on. And

also, what exchange rate are you going to use if you don't have an underlying stable coin, which is quite often in most countries the case. So what you came up is with a payment link where you add the recipient in the address bar and you define with query parameters exactly what tokens you accept on what chains. You can send it over in a message in a QR code whatever and that's what the person sees. They then go on and pick the token that want that they want to pay with. So, we scan the wallet, we show the tokens, they pick one token, they don't have to think anything, and we simply swap and pay me in the token that I want with the token that the

other person wants to send. We we're aggregating all the dexes, all the tax aggregators, all the bridges. So, you simply pick what you can and we sort of figure it out uh by ourselves the best route. Uh next up, another problem was human readable receipts. you sent your friend a block explorer page and it was really hard to get figure out what actually happened and it's getting harder and harder with all the tools and bridging that you can do these days. So we simply added a human readable receipt and another nice little thing human readable preview card so if you share it in telegram it automatically shows you what you got.

Then the second issue is and that's where everything sort of started get together is that these URLs get very long and out of sync. You send a link and one week later you want a different chain. So we had to take it out and then we thought okay where do you actually keep these payment preferences in a decentralized way? Now we found a solution there is a place and that is ENS. That was the beginning of our love story with ENS. Uh we basically realized every ENS address has text records or other data records. That's where we store the avatar image or the avatar URL or URL or your description. These are these text

records that come along with your ENS record. And we simply took one said if you put a JSON configuration inside the MI.Yodel Yod record then we automatically fetch that every time somebody opens your link and we preconfigured a page. Next up we said hey let's we now have a lot of space to configure stuff. Let's just use everything and put it into this JSON such as you can configure your own preview card designs and when you send this to somebody, it looks nicer, which is great for little shops to make it

more viral. Next up is notifications. How do I know that I'm getting a payment? So, we added web hooks. You add a record uh attribute web hooks into the record and then we simply index the payment. We look who got the payment. We resolve the prime ens look does he have a web hook and if yes send them a notification. With that we basically build telegram bots, slack bots, all kind of bots integrations and so on. And you can use everything customize it to your needs in a fully decentralized way.

So, one party that used that pedal battle uh auction, you can bid on prices, great tool. They're using most of our things. Uh super happy. So, they basically how do I notify my people that people paid? So, they just use the notification and telegram group and everybody knows and can start doing their bidding wars. They also use different receipts all the time to make it a bit more fun. Now, next problem is I'm using it more and more. How do I actually keep track of my friends and how do I save them in my address book in a decentralized way?

So, last year I went to ECC and I saw a presentation of EFP, Ethereum follow protocol and here we are. It's basically a social graph where you can follow other ENS addresses and it's basically shared across you can access it anywhere. With that, we had out of the box an address book that you can share, take with you into other apps, and you're not logged in to our system. And eventually, we realized it's not just an address book, but it's actually a trust score. So, when you're sending money to Vitalic and you made a typo, you will instantly see it's a typo, it's a scammer, has got no followers or the

followers are all scammy. So for that we have a payment flow that you now have a trust score that makes it easier you know to know is it the right person. Now next problem. I'm getting thirsty. That's the next integration we did. It's a self-s serving beer tab. So here you can put it somewhere. You scan a QR code or open a mini app which is the next thing that I'm going to show. and you make a payment through the Yodel app.

And once it's done, the beer tap unlocks. You can tap your beer and pour your beer. Now, this uses most of the same uh system I showed. It's a web hook. Once it's paid, it gets notified. It happens pretty fast. And then it unlocks the beer cap. Uh yep. Uh just a quick graph how how that works. We basically every time you make a payment there's an event being emitted which our indexer indexes completely analyzes the transaction puts everything into the back knows exactly

what currency you paid in what token and so on. resolves all the ENS record from the sender, from the receiver, from the mini app, from the community to then trigger the correct web hooks and so on. Once that index and there is a web hook defined, we call that up uh so they can do whatever they want. Now, how can you open one of those yaps or mini apps as we call them? You simply configure an ENS address again, set up a URL that then you then we open inside our super app as an iframe or a web view or whatever.

And with that all you have to do is then if you like it you can follow it again on ENS as your social graph and then it's being put on your home screen so you can easily access the kind of mini apps and apps you're expecting like beer tabs or where you don't pay with actual tokens but with like a beer token that at a conference you can airdrop to the people directly and if they have the token they pay with the beer token. Otherwise, they use regular money. A priority inbox where you charity gate access to your inbox, so you have to pay $10 to a charity. So, you sort of have a spam protection for

the VIPs, loyalty stamp cards, reward system for merchants, bill splitting, poker buying, pay out, dashboards, all kind of interesting stuff. So, if you need ideas, just let me know. I've got plenty. Uh we like to work together with network cities, pop-up cities, events, meetups, uh side events to sort of build these little mini apps together, reuse them. We have launched one in Brazil called EP City. Uh big success, 100 members and they've basically developed 15 yaps together, deployed them, made $4,000 in transaction volume. uh and now you can

sort of start taking them out and re and bring them into different communities and reuse them. So with that the the network city got their own little super app within our super app completely white labelled to their tastes. Yeah, that's it. Uh if you want to build we've got a telegram group that's the best spot where you can ask everybody follow me or ask questions. [Applause] Any questions for Sebastian?

Thanks. Hi. So, I have two quick questions. The first is, so I'm not a crypto OG and last year I was considering buying my ENS address and they're so expensive. I love the idea. And so my first question is how are you going to deal with you know lots of people not being able to afford or wanting to buy an ENS address. And the second question is maybe related. If I understand correctly in this transaction only the recipient needs to have set up their preferences and their uh you know uh text record on ENS. So, like in theory, if the shop is willing to invest the money to buy an ENS record, they would be able to receive payment in

their favorite tokens and the customers wouldn't have to actually have an ENS themselves. Is that correct or is that not correct? Okay, so the sender, they don't need an ENS anyway. They can just connect and pay. the receiver also doesn't need but then they can't control the way money is flowing basically so it's up to the receiver. Uh, regarding the question of the coast, yeah, that was an actual problem, especially back then when it started. Uh, but now there's lots of ENS subnames such as basees, uni.

Everybody basically can get a free ENS address. Uh, also there's lots of tools that projects and communities can have their own subname such as epaccity. They're using a service called just the name. It's uh to basically let the people get their ENS subnames for free. So I will be sebastian.cd.e. I can configure it there. So that's sort of solved. Now you won't get your ease your prestigious one but typically you just get a cheaper one. Yeah. Uh and it's a very nice API sort of abstraction because you can really have ENS subnames

the the way you like it. Some people don't care that much about decentralization and just want a free one that works like with just a name or they want to have it register on a cheaper L2. there are services for that namechain supposedly will make it cheaper uh and so that's sort of a thing that'll eventually go away and it's becoming a non-issue if you ask me. The first question was the second Oh yeah yeah yeah cool.

Do I get any other questions for Sebastian?