Cellbits.com currently offers 9 screen sizes for cell phone wallpapers, screensavers and background downloads. See the partial list below for mobile phones that have these screen sizes. Consult your operators manual or cellular carrier website if you don't see your phone listed. Custom sizes may be available. Contact: customer_service with requests.

Android Phones
The Android phone operating system actually requires a wallpaper background larger than the listed screen size because of the sliding desktop or multiple home screens  it can use. So, 320x480 screens need wallpapers that are 640x480,  for example. For screensavers or live wallpapers, the actual screen resolution is used. For example, an Android device with a 480x800 would use a screensaver of that size. Many Android screensavers are "one size fits all", and adjust to your screen size. Some are set for specific screen resolutions.

320 x 480 (640x480)
Acer: beTouch E400
Garminfone
HTC: Aria,  Droid Eris, Freestyle, G1/Dream, Hero, Legend, Magic/MyTouch, Slide 3G
LG: Andro-1, Etna, InTouch Max, Optimus, Phoenix, Swift, Thrive, Vortex
Motorola: Backflip, Cliq, Cliq XT, Devour, Droid Pro, Flipside, Quench XT3
Samsung: Behold II, Galaxy/i7500, Moment
Sharp: Kin Two

480 x 800 (960x800)
Acer: A1, Liquid E
Dell: Streak
Google Nexus One
HTC: Desire, Evo, Incredible
LG: Ally, GW880, Optimus Q
Samsung: Fascinate, Captivate, Vibrant

480 x 854 (960x854)
Huawei: Honor U8860
Motorola: Bravo, Defy, Droid, Droid 2, Droid X, Droid XTreme, Milestone, Milestone 2, MT716
NEC: Medias WP N-06C
Sharp: ISO5
Sony Ericsson: Urushi ST18i, Xperia Arc/ Arc S, Xperia Neo V, Xperia X10

540x960 (1080x960) qHD
HTC: Amaze, Evo APX515CKT 3D, Evo Design, Hero S, Sensation, Vivid
Motorola: Atrix, Atrix 2, Droid 3, Droid Bionic, Droid Razr, Droid X2, Photon/Electrify
Sharp: Aquos IS13SH

Feature Cell Phones

240 x 400
LG phones: AX-840 Tritan, Banter Touch, Chocolate Touch, Cosmos Touch, CU915, CU920, CT810 Incite, CU915 Vu, CU920 Vu, dLite, Encore, GR500 Xenon, GS390 Prime, GS505 Sentio, GT505, GW520, KB770, KC910/910i, KE850, KE990/990c, KF900, KP501, KP502, KU990, KP500 Cookie, KP501, KP502, KU990/990i, LG-KP570, LG-9700, ME850d, MX830, U990, Touch 8575, Rumor Touch, UX-700 Bliss, UX-830 Glimmer/Spyder/Vantage, UX840, Vu Plus, VX9700 Dare, VX10000 Voyager
Motorola phones: Crush, Evoke QA4, Krave ZN4
Samsung phones: Eternity II, Flight II, i-910 Omnia, Intercept, M8800 Pixon, Reality, SGH-A867 Eternity, SGH-A877 Impression, R810 Finesse, R850 Caliber, SGH-A887 Solstice, SGH-S5230 Star/Tocco Lite, SGH-T929 Memoir, SGH-T749 Highlight/Spark, Solstice II, Sunburst
Pantech: Ease
Sharp: DM002SH, FX, W41SH, W42S, W51SH, W52SH, W61SH

240 x 320
Asus: Galaxy II, P550, M930, P526, P527, P552, P735
Audiovox: CDM-9900
AT&T: 8500, Tilt (8925) & (8925a)
Blackberry / RIM: Pearl Flip 8220
Casio: Boulder, Ravine, Rock
HTC: Tatoo
Kyocera: NEO e1100
LG: 3125, CU720 Shine
Motorola: Razor V3, V3xx/xxR, V9, V9x Z9...
Nokia: 5700, 6120, 6121, 6126, 6555, 6650, 6790 Surge, C3-01, E51E65, N73,
N75, N76, N81, N82, N95
Pantech phones: Duo, C820 Matrix Pro
Samsung: A717, Sync A707
Sony Ericsson phones: A100i, A130i, A260, A270, C123/123A, C510a, C702, C902, C903, C905/905a, G502, G700, G900, K770i/770iv, K790, K800,/800i, K810/810i, K850i, M600, M608c, P1i, S500i, S700, S710a, T650i, W518a, W580i, W880,/880i, W890/890i, W900i, W910i, W950/950i, Z750a, W770i
Vertu: Ascent, Signature

320 x 240
Blackberry: Curve, Curve 3G, 8300, 8310, 8330,  8500, 8520, 8530, 8700, 8800
LG: CB630 Invision
Motorola: Karma QA1, Q Global
Nokia: E61/61i E62, E71x, N71
Samsung: A827 Access, BlackJack/BlackJack II (i617), SGH-i637 Jack

176 x 220
Audiovox: 5600, CDM-8940, CDM-8945, CDM-9500
LG: 535, CU515, MM-535, VX7000, VX8100, VX8600
Motorola: A840, C698p, C975, E770, E815,  i550,  i600, i605, i680, RZR, SLVR, V3r, V330, V540, V551, V710
Samsung: a790, a890, a920, a940, i600, p207, SGH-A177, SGH-A517, SLM (A747), UpStage
Sanyo: 7400, 8300
Sony Ericsson: 750i, F305, K700, K750i, K578c, V600i, V630, W302, W380a/380c/380i, W395, W550c/550i, W600i, W610/610i, W660i, W700, W810/810i, Z610, Z710i, Z800

128 x 160
Audiovox: PM-8920
LG: 1150, 1200, A7110, C2000, CG300, F7200, F9100, L1400, L1400i, VX5300
Motorola: 300, C257, C290, L2, L6, V190, V235, T720, 720i
Nokia: 6061, 6085, 6102, 6102i, 6651
Pantech: C150
Samsung: A117, A127, A437, C417, D347, D407, D357, E316, SPH-M310 (Slash), X426, X507, V206  
Sony Ericsson: F500i, K510, R300, T610, T637, W300i, z310A, z520/520a, Z525, Z600