The app opens, shows me the Mojang with white background, asks me for my iTunes account password and then closes the app. I tried restarting my phone but that hasn't worked. It also didn't let me write a review on the App Store(I hadn't heard of this website) as it tells me I cannot write a review without purchasing the app. I have had Minecraft on my phone for over a year and a half, and have never had this problem.
Thank you for your report!
Issues such as these are often due to a temporary service outage, and should be back up and working again soon. Please keep an eye out for messages from @MojangStatus on twitter for the latest status updates.
For any issues with your specific account or billing, you will need to contact Minecraft Customer Support directly, who will be able to advise you individually.
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