In a slightly surprising twist, the mobile game of Uncanny X-Men: Days of Future Past actually reflects the comic book that inspired the new film. So, staying true to its 90s roots, it comes in the form of a side-scrolling beat-em-up (with just a hint of platforming).
Controlling one of five (soon to be eight) interchangeable characters, players will travel between a futuristic, apocalyptic setting - home to Old Wolverine and what remains of the X-Men - to the time in which the X-Men were in their heyday (albeit still disliked by humans), to prevent the mutant oppression and decimation that will occur unless they change the past.
Much like the original 90s smash-hit arcade game X-Men - and it's mobile port in 2011 - Days of Future Past pits players against countless identical goons as they hack-and-slash their way to the occasional big boss fight at the end of each stage. In terms of controls, Days of Future Past works off of a simple button layout - with a backwards and forwards arrow, an attack button, and a jump button. Despite the attack button being able to react to various swipes in the form of special moves, it still boils down to the same tired button-bashing until enemies decide to fall down and dissipate into nothingness. When coupled with the sheer ease of this game, it makes for a painfully drawn-out experience.
GlitchSoft has included bouts of platforming in the hopes of keeping things interesting, with the ability to jump and double-jump allowing players to access new areas and platforms with all kinds of XP goodness - though its more functional rather than a source of entertainment or a challenge. The XP can be redeemed in exchange for upgrades or alternative costumes, which is okay for a bit of a novelty.
The cutscenes and character interactions are entertaining, though, guiding players through the story (which could obviously ruin parts of the movie if they've been avoiding all promotional content, so a word of warning to those who don't want to know anything) and introducing various versions of different X-Men.
Days of Future Past is fine as a bit of a warm-up for the movie or an homage to the fan-favorite comic, but otherwise its just too bland of a side-scroller to be anything more.