Hi @Mazandaran,
thanks for your feedback. I hope you understand that we can't instantly create a perfect product, but we are willing to improve and try to fix upcoming problems as quickly as possible.
1) We did not experice any issues with F-Droid so far. Please let us know if this problem persists. Does it freeze each start you start it?
2) See this topic:
#99
3) See this topic:
#202
Regarding the broken restart after freeze: this is clearly a bug. Can you provide us system logs? We will be happy to fix it in the next release.