Coinomi is also closed source.... if it is a problem for OP, he really should avoid mobile wallets for altcoins imo.
This problem with coinomi only happened in desktop version, which is not the case of the OP.
I read this a few time ago, and this "critical vulnerability" probably never happened and it happened only in desktop version (which is not OP case)
Hi bitmover, the desktop issue you mentioned was fixed immediately, but it was concluded that no user lost funds due to it as it could not have been exploited. The user who reported it was trying to extort Coinomi, you can read the detailed forensic report here:
https://twitter.com/kimionis/status/1131945228506738688.
I like coinomi and I have no problems with it, but I would never trust more than the price of my smartphone in a mobile wallet.