Usability 
FunForMobile.com is an interesting MoSoSo (mobile social software) site. Like Zedge.net (review) and mobile9.com, it provides a handy way to send ringtones, videos and wallpapers to your phone. With the carriers greedily charging as much as $2.50 for a ringtone which expires in 90 days! sites like FunForMobile should be getting lots of traffic. You upload your content to FunForMobile's PC site and download it to your phone from their wml WAP site wap.funformobile.com. FunForMobile can also send the content to your phone via MMS.
The site transfers files you have already converted to mobile format, it don't seem to have any online conversion or editing capabilities like, for example, mobile17.com. What FunForMobile does have is concise and clear instructions that explain how to use free desktop applications to convert mp3's or tracks on a CD to a ringtone format that your phone can handle. Another tutorial details the process of converting videos to .3gp again using a free downloadable converter. There is even a phone capabilities database that tells you the formats that your phone accepts and an active user forum where you can ask for and actually get help.
Another thing that sets FunForMobile apart from other similar sites like Zedge and Mobile9 is that it has a significant mobile web presence. When you register you get a PC blog which has a mobile edition. The blogs display your profile, posts and a gallery of your uploaded files. The PC version can be customized with images and colors can be changed using css. The blogs accept comments but do not have rss feeds! Other social features include a friends list and the ability to send private messages and share content with other users. Uploaded files are public by default, although you can flag them as private. Sharing is a step beyond public where you send a link to one of your files to another FunForMobile user.
One thing that bothers me is that FunForMobile requires your mobile number as part of the registration process. I think it's risky to give your mobile number to anyone you don't know. I worry about SMS spam and getting hit with premium SMS charges. just to be clear, I consider FunForMobile to be trustworthy and have no reason to believe that they will do anything improper with a user's phone numbers. The site has a good privacy policy and promises not to share, sell or misuse your information. Still, what happens if FunForMobile and it's database of mobile numbers is sold to someone unscrupulous? Being able to receive files by MMS is a desirable feature for some users and it obviously requires giving the site your number. But the number shouldn't be required as it's not needed if you only want to download from the mobile site. If you aren't using the MMS feature. I recommend giving an obviously bogus number as the numbers aren't verified.
It's not even necessary to register in order to download, the PC site is searchable and you can download files to your PC for side-loading or get a number which you can use to download a file from the mobile site.
Their are actually multiple mobile sites.
I ran into some errors using the mobile pages. Some of the pages are just too large to load on most phones, for example the "Popular Pictures" page which has just three (NSFW) animated gifs on it which add up to 545 KB!. With many browsers unable to handle pages over 20 KB this is just not going to work. I also got intermittent compile errors loading various pages on FunForMobile's sites. I traced these to some bad markup in the third party ads displayed on the site. The ad text occasionally contained "naked" ampersands like "Fun & Games For Your Phone" Xhtml requires ampersands to be displayed using the html entity &. The ads change every time you load the page and only a few of them had this problem so refreshing the page usually made the error disappear.
This review may sound negative but I actually think FunForMobile is one of the better mobile social sharing sites and that the issues I mention are minor and have workarounds. The mobile side, particularly the mobile blogs is relatively full-featured in contrast to Zedge and Mobile9 which are strictly PC Web social communities with the mobile site being just a way to download files with no mobile social interaction at all. FunForMobiles's mobile blogs seem to be well used and relatively full-featured.