A slide deck from SF Bitcoin Devs talk about typical mistakes that should be avoided when building cryptocurrency wallets.

1. Growing a Cryptocurrency
Beyond Early Adopters

2. Who Is This Guy
world’s first bitcoin merchant service
world’s first multi-currency wallet
world’s first blockchain SaaP
Founded:
2013
2014
2015
Started playing with consensus algorithms in 2010

3. Launched in 2014
Ethereum-based altcoin
~10 integrated trading
platforms
USD & EUR on the Blockhain
Protocol: Omni Layer
(ex. Mastercoin)
Launched in 2015
~40,000 users
Protocol: Ethereum contract
5 integrated projects

4. Tether Ecosystem

5. Elcoin Ecosystem

6. Cryptocurrency
Adoption Barriers

7. Problem: wallet download

8. Solution: web wallets

9. Problem: User-side Keys

10. Solution: in-browser key derivation

11. Problem: Lost Password

12. Typical proposal:
multi-sig & recovery keys

13. Better Solution:
Automatic Recovery Key Backup
Wallet Provider
Recovery Service Provider
User
Multi-sig Wallet

14. IT WORKS!
secondfactor.io
+

15. Wait!
Did you say multi-sig
wallet for Ethereum?!

16. Our Little Secret: Blind Signing
SecondFactor
Ambisafe Wallet API
Protocol
ImplementationSighash(es)
Sighash(es)
Simple
ECDSA Sign
Simple
ECDSA Sign

17. Problem: “Fee Currency”

18. Solution: Wallet Provider Covers Network Fees

19. Bitcoin-based USD Wallet
No Mention of Bitcoin

20. Ethereum-based Wallet
No Mention of Ethereum

21. Problem:
Newborn Cryptocurrency Requires:
Web & Mobile Wallets
Trading Platform Integrations
Merchant Services
A ton of other integrations
WE HAVE SOME OF THESE

22. Solution:
Standartize Wallet API’s
Supernode Standard
Initiative
Our Try:
https://www.ambisafe.co/blog/supernode-standard-initiative/

23. Vitalik Buterin: ah okay, so it's a wallet which can very quickly be
configured to work with different block explorer APIs for different
cryptos
Vitalik Buterin: interesting
Ambisafe
Keyserver
Web UI
Other Integrations
Your
Currency
Currency Plugin API

24. How is this decentralized!?

26. Thank you!

27. Andrey Zamovskiy
Founder
andrey@ambisafe.co
Questions?
Johann Barbie
CTO
johann@ambisafe.co