Hello Daniel,
I understand your concern. Please let me know if you are trying to download AVG from your AVG MyAccount or Google Play Store. Please send us the screenshot http://avgclick.me/getscreenshot of the error message you receive. We can check the same and assist you further.
I can download but when I try to open file my phone says I cannot open avg
Daniel, if you provide us with the screenshot it will be easy for us to assist further.