Wallpaper App UX & Performance Review

I’ve just released my new Google Play app, “Nature Wallpapers” (publisher: Livelyup IT Solutions), and I need a fresh, detailed critique before the next development sprint. Please install the live version... (Budget: ₹600 - ₹1500 INR, Jobs: App Development, Graphic Design, iPhone, Mobile App Audit, Mobile App Development, Mobile App Testing, Usability Testing, User Interface / IA)