Dear, Client!!!
I have checked your job description very carefully and I am sure I can fix the bugs of Gridview within 2~3 days.
As a professional iOS(Objective-C, Swift 2.0, 3.0)app developer with more than 5+ years experience, I have high skills in iOS app development and backend such as Firebase, backendless etc.
And I have used back-end integration with REST service as well as direct DB calls, Geo location, Geo fencing, Payment integration, facebook/twitter/instagram, and lot of other technologies in my apps.
So I am sure I can deliver good product within correct deadline, if you hire me.
Thanks for your time.
Have a good day.