Fix 2 errors in the app

I need some Android expert to fix 2 errors in my app. 1. There are 2 situations when it can happen. First is when I use it today, click read more and read more. And then just close it by clicking the Home menu button on my phone. If I open it again in few minutes, no errors and I see that post I had read. But if I open next day it shows an error. I click Ok and the app strats again without an error. Second situation is when I use different wi-fi zones. For example I opened the app in one zone, closed it and in 10 minutes opened it again in another wi-fi zone. Then it shows the same error. I think we can make something like this, I saw some apps did this. After I click Home menu button it shows pop up and ask me to exit or not. If No, I'm still in the app, if Yes, it kills activity and when I open it again even in 5 minutes, it starts from the begining. Or maybe you have your own suggetions about this. Let me know about this issue what are you going to do, so I will decide who is winner. 2. The app doesn't see mobile Internet. It works now only with Wi-Fi connection. I want you to fix it and make the app to work with mobile Internet.