Thanks to the official WinZip app, you can open compressed files from an email, explore the elements they contain, open encrypted files, and even preview elements inside them, in one of the following formats: txt, doc, docx, xls, xlsx, ppt, pptx, rtf, pdf, key, numbers, pages, htm, jsp, bmp, jpg, jpeg, tif, tiff, png, gif.
The application has a pretty simple interface from which you perform all the tasks you need. The only problem is that, by default, WinZip does not support files in RAR format. If you want to decompress a file in that format, you'll need to buy the license.
WinZip is a very useful app since it helps you work easily with compressed files. Never again will you receive an email with an attached compressed file without knowing what to do with it.
Requires Android 2.3 or higher