This is really a nice app, developers are above board there. and its improving but can you add one extra option like 1) sent messages can be unsent or removed from the person's chat box . and 2) make it time-locked encryption algorithm!(encryption - time-locke) because when user set a time period just like 10 sec or 10 mint or 10 hour . it will delete (decrypt at a certain time period ) automatically after finishing given user time period.
hope you like my advice :)
but over all really nice app
waiting for next chapter
keep moving foreword
thank you