How can I view a 3gp downloaded file with HTC Tattoo mobile?

The program allows you set the output file format and the saving position. Choose the output files format under the list of Format of the main interface. At the same time, you can click the button Browse to specify an output folder on your Mac OS X.you can try use the uSeesoft Total Video Converter

DVD Converter Software converts DVD movies to AVI, MPEG, WMV, XviD, DivX, iPod, PSP. 3GP, MP4, VCD and SVCD formats.

it can convert video files at super fast speed and best video quality.
It can convert video file between any video format such as converting AVI to MPEG, MOV to 3GP, WMV to MPEG, MKV to AVI, MKV to MP4, etc.
so you can visit here to know more information about it
you can try use the uSeesoft Total Video Converter
it can convert video files at super fast speed and best video quality.
It can convert video file between any video format such as converting AVI to MPEG, WMV to AVI, 3GP to MPEG, MKV to AVI, MKV to MP4, etc.
It can transfer all iPod content to the iTunes on your different computer, including iPod music, movies, playlists, videos, podcasts, ratings, last played, and more.

Fast, easy to use DVD ripper to rip DVD, convert DVD to DivX, DVD to Xvid.

Now all files are on your computer and iTunes, you can sync your iPod with it smoothly without deleting any files.
TOP Video Converter can help you, and it can help convert various videos, of course including 3GP files, to all the popular video formats, like AVI, MPEG, WMV, FLV, RM, MKV, MOV, etc. Wonderful performance and super high converting speed.
You can try Cucusoft DVD and Video converters suite which includes Cucusoft Ultimate DVD and Video Converter Suite.
It is the best all-in-one DVD and video conversion software converts DVDs and videos to play on almost any portable device including iPod, iPhone, Zune, PSP, video capable MP3 players, video capable mobile phones, and Pocket P.C., etc.
Unbiased reviews and side-by-side comparisons of DVD video converter suite give you enough information to research the ins and outs of a particular product

Many of you may wonder why there’s a need for a DVD to iPod converter.

I want to share Aiseesoft Total Video Converter
It can convert video to MP4/MKV/WMV/AVI , 3GP, H.264/MPEG-4 AVC, FLV, MPEG-1, MPEG-2, 3GPP, VOB, DivX, Mov, M4V, DivX, XviD, ASF, SWF, VOB, DV, Super VCD(NTSC, PAL, SECAM), VCD(NTSC, PAL, SECAM) , DVD(NTSC, PAL, SECAM) and HD video etc
If you want to convert a few minute, I recommend you to try 4Videosoft 3GP Video Converter.It can convert all the regular formats, such as FLV, WMV,MOV,AVI to 3GP, 3G2 video.You can free download it to have a try. I had converted a two-minute video for my friend.