Keeps crashing – Pokémon GO Review

I love this game, but ever since the new update my phone will only ever crash when Pokémon go opens. Maybe it’s a IOS version issue since I have an iphone6, but I don’t know. If there is any reason for this or anything I can do please let me know. I’ve looked online and nothing seems to be working.
Review by Boston S on Pokémon GO.