Hi
I see you have already got your Contact Form defined. Email on Android can be tricky, as you have discovered. There are a number of extensions you could try and in this case an extension is probably the best solution.
Note, your Button1.Click block is wrong. You cannot use "open another screen" for Screen1, it already exists - therefore, everytime the button is clicked, an additional Screen1 is created! Also, the current Screen is left hanging in memory.
If you use this:
The User will be returned to the Screen that opened the Current Screen automatically.