Ask your client to list down the complete requirements and flow first then determine roughly how much time you need to spend on the development then based on your rate and give them a reasonable quotation.

We really unable to tell you unless we know how much time you will have to spend on the development.

I just give you an example on how you can roughly calculate the cost:

Let's say you are now working in a full time job with about 40 hours per week (8 hours x 5 days). Your monthly salary is RM 4500.

Let's say you have the complete requirements and the flow, you estimate that you will need 2 weeks of time (or 80 hours) to complete the project.
Assume there are 4.5 weeks in a month.

Your rate per week is RM 4500 / 4.5 = RM 1000.
So, the project cost should be at least RM 1000 * 2 weeks = RM 2000.
But since this is a one time off project and they do not offer you any benefits such as insurance and allowance. You should charge more than RM 2000 (eg: RM 2500).

Don't be afraid to be taken advantage of when you are still building up your portfolio. You will learn from experience and increase your rate in the future when your clients trust you.

This post has been edited by mobileoop: Sep 26 2014, 07:16 PM

The question is quite subjective as it depends on how good is the developer and also the complete requirements from the client. If it is just a prototype app that gets data from server and displays on the app, it can be developed within a week time.

I have received a few requests to build a "simple" XXX app. After I try to get more requirements from them on what do they expect to see on each of the pages of the app, that's when you will understand the complexity of the app. Usually, they will have many tiny requests like: When I tap on this button, it should animate the whole screen and etc... I should be able to swipe the top of this screen and the the next screen will be ....

Phew.. I actually have to spend a lot more time on those tiny requests rather than the main function itself. Some of those tiny requests can not be developed easily due to some technical challenges. The clients do not understand the technical challenges and thought those requests can be implemented easily.

The funny thing is I actually received a request to build an app like HungryGoWhere. I told him honestly that HungryGoWhere can not be built easily and it has been build since 2006. It is almost impossible to replicate exactly like HungryGoWhere with limited time and limited budget. I told him that if he wants me to develop the app for him, he has to give me the complete requirements or divide the requirements into a few phrases. I can help him to develop from another phrase to the next. Without those requirements or a clear scope, I am not going to take the projects as the scope of the project can be limitless.

If you ask an app developer to build HungryGoWhere app for you (without a complete requirements/clear scope) is almost like asking a web developer to build a Facebook for you.

Exactly. Those small tiny details things are the hardest to implement. The entire navigation/flow of the apps might need to alter just because of those "tiny" requests. That's the reason the complete requirements with the complete flow and expected actions for each screen is very important. Without that, I rather not taking the project.

100% agree. Mobile development is not like creating a powerpoint slide. Those gesture recognisers and the transitions animation from one screen to another might be hard to implement. But, most clients who are new in this industry will not understand those technical challenges.