It is the smallest memory card available commercially, . At 15 mm × 11 mm × 1 mm (about the size of a fingernail), it is about a quarter the size of an SD card. There are adapters which allow a microSD card to be used in devices intended for SD, miniSD, Memory Stick Duo and even USB

TransFlash and microSD cards are the same (each can be used in devices made for the other), except that microSD adds support for SDIO mode, enabling non-memory cards like Bluetooth, GPS, and Near Field Communication devices.

A point of confusion can come from the difference in the microSD and the newer micro SDHC format. The SD and SDHC share a same form factor, but not all devices are compatible with the newer high capacity format. This is even true with devices that have been developed by SanDisk such as their e200 series of MP3 players. Using 3rd party firmware however, SDHC reading capabilities can be possible, but requires an external writer

Manufacturer support

The microSD format is supported mainly by mobile phone manufacturers, among which Motorola was the first to adopt. Garmin makes GPS receivers with maps on microSD cards.

Devices

• Archos: 605 WiFi (4 GB flash version), 405
• Alcatel: OT-E801, OT-C717 Black Soft Touch
• BenQ-Siemens: EF61, E71, EF81, EL71, S82, SFG75, S88, CL71
• BlackBerry: Pearl (8100, 8120, 8130), Curve (8300, 8310, 8320, 8330), World Edition (8800, 8820, 8830)
• Cingular 3125
• E-TEN: glofiish X500, glofiish X500+, glofiish M700, glofiish X800
• FIC: Neo 1973T, Neo Freerunner
• Garmin hand-held GPS: Edge 605, 705, eTrex Vista Cx/HCx, Legend Cx/HCx, Venture Cx/HCx, GPSMAP 60Cx, 60Csx, 76Cx, 76Csx, StreetPilot i2, i3, etc.
• High Tech Computer Corporation (HTC): HTC Artemis, HTC Atlas, HTC Breeze/HTC MTeoR, HTC Cavalier, HTC Elf/HTC Ted Baker Needle/HTC Touch, HTC Elfin/HTC Touch, HTC Erato, HTC Excalibur, HTC G1, HTC Herald, HTC Hermes/HTC TyTN, HTC Iris, HTC Kaiser/HTC TyTN II, HTC Libra, HTC Love, HTC Monet, HTC Touch Neon/HTC Touch Dual US, HTC Nike/HTC Touch Dual, HTC Omni, HTC Pharos, HTC Polaris/HTC Touch Cruise/HTC Touch Find, HTC Raphael/HTC Touch Pro, HTC Startrek, HTC Titan, HTC Touch/HTC Vogue, HTC Vox, HTC Wings
• i-mate: Smartflip, JasJam
• iRiver: E100
• JVC: GZ-HD5, GZ-HD6
• Kyocera: KX55XO, Slider Sonic, Slider Remix
• LG Electronics: VX8300, Chocolate (VX8550), VX8700, enV2 (VX9100), Dare (VX9700), Voyager (VX10000), Viewty (KU990), LGCU515, Shine (KE970), Rumor (LX260), Scoop (AX260), UX260
• Motorola: V360, E398, V635, V710, A780, E815, A840, E770, E815, E895, C975, V975, C980, V980, A1000, A1200, M1000,Maxx Ve E1000, V1000, ROKR, V1050, V1150, SLVR L7, Motorola L7e, E1060, E1120, RAZR (V3i, V3m, V3r, V3t, V3x, V3xx, V6), i870, i880, i876, i876w, i885, i580, A1200, KRZR (K1, K1m, K3), Z3, Z6, Z8, Z9, Z10, L7, Moto Q9h, Q9c
• NEC: N908
• Nintendo DS storage devices (e.g. DSTT)
• Nokia: 3109c, 3110c,3120c upto 4GB 3250, 3500c, 5200 (up to 2 GB), 5300, 5310 (up to 8 GB), 5320 (up to 8 GB), 5500, 5610, 5700, 6085, 6086, 6110 Navigator, 6120/6121 Classic, 6124 Classic, 6125, 6131/6126/6133, 6151, 6233, 6234, 6265i, 6267 6275i, 6300 (up to 2 GB), 6301, 6500 Slide, 6288, 6555, 7373, 7390, E50, E51, E61i, E65, E71, E90, N73, N75, N76, N78, N81, N82, N95, N96
• O2: O2 Ice, O2 Cocoon, Xda Orbit, Xda Orbit 2, Xda Exec, Xda Mini S, Xda Trion, Xda Stellar
• Orange: Berlin
• Palm: Centro, Treo 800w
• Patriot: PC133
• Pantech: Duo
• Pioneer: AVIC-S1 Mobile Navigation System
• Sagem: My V-76, My X 6-2, My501C, My401C, My411X, My511x
• Samsung: Samsung Instinct, SGH-A717, SGH-A737, SGH-F210, SGH-D600, SGH-Z370,SCH-U620, Samsung SGH-E250, SGH-E740, SGH-X836, SGH-U510, SGH-U900
• SanDisk Sansa: e200 series, c200 series, Express, Fuze, View
• Sanyo: SCP-8400, SCP-8500 (Katana DLX)
• Sharp: 770SH
• Song: Song DIC 338/A138
• Sony Ericsson: K850, XPERIA X1
• T-Mobile: Dash (Smartphone), WIng (pocket pc), Sidekick 3, Sidekick LX, G1
• Vodafone: Vodafone 1210, Vodafone 720, Vodafone 716, Vodafone 715, Vodafone 810, Vodafone 527