Telegram Based App. Bug Fixing and Final Check

For those with experience working on Telegram app. I have a telegram based app. Need to make 3 minor bug fixing. Payment will only be after completion. The Bugs 1. Frozen screen upon startup. (there is a blue demo showcase that shows features of the app upon startup. Its not working properly. Remove blue demo screen or fix it) 2. In chat dialogue, last seen below contacts name doesn't scroll. It's static so can't see the time. I will share a screen shot. 3. I can't send sms invites to existing members of telegram. They may not be under My New App. Contacts search and invites should be separate. 4. To check on 5 items such as in app purchase, expiry of app and some post data information.