Applications that can read GEDCOM files:
There are a number of Windows and Android phone and tablets applications available that can read a GEDCOM file. These range from fully fledged family history editors and databases to simple GEDCOM viewers. Quite a lot are free.
Note: If you want genealogical applications for iPad's, iTablet's or Apple computers, they're there but you're on your own finding and evaluating them.
Most popular family history editors have a free version which are usually a cut down version of the paid version. I’ve found these to be very useful as most of the functions are there, the paid version having more exotic functions available that you may never need.
For Windows:
Personal Ancestral File (PAF) was a genealogy management software product formerly provided free of charge by FamilySearch.
It's fairly easy to use, certainly good enough with lots of features for anyone starting out.
It's still available for download here.
RootsMagic 7, family history editor.
More information and download it here.
The paid version of RootsMagic is reasonably priced at USD29.95.
Ancestris64, a free very powerful family history application but very complicated it setup and install.
More information and download it here.
Family Historian is a very powerful genealogical application, the full version is a bit expensive but worth it if you get serious
More information and download it here
My Family Tree for Windows 10. A free Family history program from the Windows store.
Easy to use with some excellent reports. You can get it here.
This list is far complete, there are a lot of genealogical applications available for Windows, check here for a comprehensive list.
For Android Phones and Tablets:
Family Tree Maker - FamilyGTG
A useful application that will display you a chart from a GEDCOM file that you can print in pieces then join together to make one big chart.
More information and download it here.