The camera only shoots at resolutions up to 2-megapixels which is entry level for a mobile phone these days. Outdoors it performed reasonably well. The white chair is a little bluer than it should be but I have seen worse. The daffodils were photographed quite close up and their detail has been reproduced fairly nicely. There was a small breeze causing them to move, though, and you will notice that some are a little blurred as a result.
Indoors I found shots to be grainy and dull. The coloured dish, photographed under normal household lighting is a good example of the problem.
The camera includes a fairly standard array of filters, with one interesting addition. The ‘false colours' filter changes the natural colours of an object. Take a look at the extra photo of the coloured dish to see how this works in practice. One other point of note for sharp-shooters is that images seemed to take ages to save.
As an S40 mobile the on-board features aren't as expansive as those you could expect to see in an S60 mobile. The list of what is available in addition to what I have already mentioned includes web browsing, voice recording, alarm clock, notes maker, calculator, count down timer, stopwatch, to do list and calendar. PC synchronisation software and a cable are included. There is no FM radio (though the 7500 Prism does have one).
If you like the Prism range and your chosen source offers both the 7900 and 7500 Prisms then I'd advise going for the 7900 model as it has a wider set of features and better build quality (apart from the missing FM radio). If other handsets are on the table, though, I'd say you should weigh up the pros and cons of them and this mobile carefully.