Many sites are already discussing this, but be aware that the upcoming major update to iOS is transitioning the OS to a 64 bit system. This will break numerous apps unless they are updated by the developer. Out of the titles I own, over 49 will break. Some are relatively high profile, such as Icewind Dale, Baldurs Gate, Waterdeep, Infinity Blade, etc.
Ordinarily I trade in or sell my old iPad when I move on to the next one, but it looks like my iPad 12.9" will become my legacy console, as many of my older games will most likely not be updated by the developers. You can tell which apps will break by going into settings->general->applications
And BTW, don't be angry with Apple, as developers were given years of warning that the transition was coming.