Why are you not using Signal / Textsecure or any other of these new apps which have privacy in mind. IIRC they even said Hemlis won't be open source according to their FAQ so I don't think these 3 guys would've pulled this off any better than Telegram even with their dubious encryption.
I can use these apps but in order to be able to recommend it to my friends as an app that can replace Whatsapp or Viber, it should have a comparable UI/UX. I too was concerned about their source availability approach. What will you suggest that meets these criteria?
Seems they changed their mind about open source, according to the comments section[1] "We’ll release the usable parts of the code as free software with the most free license we can. It belongs to the community (and the community paid for it)."
