Web backend is the need of every apps and cannot be avoided. It gives you the access of having a central database with the help of which it becomes easy for the users to share their content with each other including Photos, messages or reviews of the restaurants. In older days, it was possible for us to develop all this on our own as we have existence of certain technologies like Ruby on Rails or PHP. But things do change with the time and it did here as well. There are certain challenges being faced which are as follows:
It demands huge time investment as the development of backend takes a lot of time.
Being a skilled front end iOS app developer will not make you skilled in back end development too. Both of it are different aspects and demands time to learn.
We never can identify or understand the exact nature of iOS apps and App store as we do are not sure if app usability will be limited or it is going to be huge with millions of users. Measuring the Scalability while developing the back end is a difficult task to be done.
To make it easy for you and sort all your problems, now there are many companies who aids in the development of back end and offers you with a premade and highly configurable web backends that can be easily integrated with your apps. These are quite popular as Backend service or BaaS.
StackMob - StackMob is called to be one of the most popular and has got high capability of customization of the offering provided by BaaS. It allows you to upload your own back end followed by creating of your own web service.
Parse - Parse is popular for the free plans offerings. The documentation here is quite simple to understand. More info.
Appcelerator Cloud Service - This is a complete package of BaaS features and its free plan is the most attractive one. It is designed in a way that makes it possible to work with Titanium SDK. More info.
Kinvey - Kinvey is majorly based on active users and allows you to have 200 active users for free every month. More Info.
Applicasa - It is almost same as others, but the only thing which makes it unique is its Drag & Drop functionality which assists in the creation of your own tables and custom objects. More Info.