Will i lose my current progress if i delete Robot Invasion Wars?

Yes. If you delete the game you would have to pick a new username and start from the beginning again.

Can i restore purchases after reinstalling Robot Invasion Wars?

Yes and no. Only some purchases are restorable.
Currently restorable items:

• Weapon bundle (Unlock all weapons)

When can i expect answer when writing an email?

We try to answer as fast as possible. But we check once a day.

Why do i have to write an username when signing up in Robot Invasion Wars?

We use the username to show your score on our global leaderboard.