Crashes

Bought 5s yesterday. Bought because my fishing forum uses it. Upgraded to is 7 this morning. Now yuku app closes as soon as you open it. Reloaded app a couple times. No help. Please help quick!

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After using a few days I believe it is crashing when using the iphone data. It works when I am at home on my wifi.

Fix this thing please.

Mljwire about Yuku