What is ruim card?
Removable User Identity Module (R-UIM, usually pronounced as "R-yuim") is a card developed for cdmaOne/CDMA2000 ("CDMA") handsets that extends the GSM SIM card to CDMA phones and networks. A removable user identity module (RUIM or R-UIM) card is an identification chip for cell phones that work on Code Division Multiple Access (. Teardown: Nano-SIM Card (UIM or RUIM type). CDMA phones that use RUIM cards share this ability to swap information between phones. BSNL's RUIM/SIM Card (Removable User Interface Module) can be used with any CDMA phones as well as EVDO enabled OMH-capable.