With iOS 8 jailbreak update being far from the official releases, the only useful things for the fans of hacks and jailbreaks are iOS 8 loopholes. Apple is killing such loopholes and the next iOS 8.1 update will reportedly come without them.
If you have first upgraded to iOS 8 from a jailbroken iPhone, iPad or iPod touch there is no need to search how to not lose jailbreak as you have already lost it. It is impossible to jailbreak iOS 8 untethered or tethered now and Apple is no longer signing iOS 7.1.2 thus you cannot downgrade from iOS 8 to iOS 7.1.2 any more.
iOS loophole in iOS 8, 8.0.1 and 8.0.2 is your only jailbreak alternative at the moment. It allows accessing some interesting options and features that are mostly available to users who are jailbroken.
Firstly, current iOS 8 loopholes allow users getting such fun games as Pokemon and Super Mario as there is a security loop in your system that allows playing in such SNES games on the iDevice without jailbreaking.
There are no game emulators in the official App Store so you ccan just use the iOS 8 loopholes to get them on your iDevice. If you wish to continue playing SNES games on the iOS 8 gadget you should not update to iOS 8.1 once it is officially released.
Secondly, there are more changes that hackers release iOS 8 jailbreak than iOS 8.1 jailbreak so better wait until they present some solution and only then decide if you wish to upgrade or not.
Users who want to use the benefits of the Date Trick loophole which will be fixes in iOS 8.1 but is still available on iOS 8 platform can change the date on their iPhone, iPod touch or iPad to September 20, 2014. Then you can disable WiFi feature and install the application such as Popcorn Time or Nintendo game. It should run without problems.