Acer A100 - Manual (Page 61)

59 Advanced settings
Clean boot
A clean boot will restore your tablet to the factory settings.
Warning! This will erase all your personal information, any contacts stored
on your tablet and any programs you installed.
Open Settings from the application menu, then tap Privacy > Factory data reset;
click Reset tablet and then Erase everything to format your tablet.
Note: If you are experiencing problems with your tablet, please read “FAQ
and troubleshooting“ on page 60 before performing a clean boot.