Phone Programming Help

[4Site]

Firstly Mods sorry if this is the wrong section I didnt want to clog up the Development and Hacking forum. Please feel free to move this to the appropiate place.
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I've got an idea for a little calculator app with specific functions which I know will go down very well with independent store owners. I've programmed a very crude prototype for Windows using my very very simplistic Visual Basic skills.

The problem is for this app to be useful I need it to run on peoples phones as a third party app so as its portable, and here's where the idea totally falls flat, with all the different platforms like Windows Mobile and Symbian i'm just wondering what would be the best platform to go for and if its possible to create a version that might work across a wide variety of different phones maybe using Java.

My ideal target audience will more than likely be Nokia, Samsung and Sony Ericsson users as opposed to Windows Mobile users.
Would it be just easier to commision different versions and how much should i expect to pay for a basic auto calculation app. I'm thinking of commercially selling the product is there any disadvantages of getting a third party to program the application?

All advice is appreciated and thanks in advance for any replies.

[levenum]

Well, I am not very familiar with the platforms you listed as preferred, but from what I know you will have to go with Java to accommodate them all.
It is still likely that you may need several versions if you want to properly accommodate the form factor of different phones.

There is no such thing as a best platform for a calculator app, which does not have specialized hardware requirements. Unless of course you are planning on a graphical interface so screen size or touch screen are major considerations.

If you really want someone to program for you for one time only, you may be interested in this site: www.rentacoder.com

As for price there are several considerations:
1) How much stuff does the app really do? How robust is it?
2) Are there other apps that preform same or similar functions and how much do they cost if at all? A quick search of the net may reveal that your idea has already been implemented as a freeware.
3) Will your software have a home? Basically when distributing commercial software you have to take in to consideration such things as registration, technical support for your customers and future updates.

Sites like www.pocketgear.com will let you easily distribute your app for as little as 5$, but many customers are unlikely to pay larger sums for an app that does not even have its own web site, let along a number you can call if you run in to trouble.

[4Site]

Thanks that was very helpful, i appreciate all the info.
Is there anybody with specific knowledge about programming for the other platforms?