some of the cellphones support 2 sim cards. You can monitor dual sim by using BlurSPY Android monitoring app. BlurSPY Rich Feature named as a sim change notification. It will give you alert when any sim changed from your target device.
Is it Possible to Spy Dual SIM on Android Phone?Melissa Limaa
These days, most of the smartphones feature dual SIM support. It has become a need of the hour for many reasons. People prefer to use one carrier for making calls and the other to use the cellular data for their better coverage and improved internet speed. Another reason why some people prefer dual SIM support is some areas have poor coverage of one network and better of the others. So they are safe in such cases. It has a good [...]