These days phone manufacturers are coming up with dual SIM phones.. A dual SIM mobile phone is one which holds two SIM cards. No doubt its very good inovative feature for people who used to carry 2 phones (a business phone and a perosonal one). Before buying a phone re-confirm whether the dual SIM is active or standby. Cheap phones may offer standby dual sim feature.
1. Active Dual SIM phone : Both the SIMs may be active at the same time. You can switch between the SIMs quickly
2. Standby Dual SIM phone - Dual SIM adapters are available in a mobile phone, and use needs to swap the SIMs from one to the other as require. Only 1 Phone is active at a time.