The present invention provides methods and devices using location detection to enable MMMDs to activate and tune to appropriate radios and networks. Some preferred embodiments use radio frequency identification ("RFID")--based location detection. Preferably, the location detection occurs at or near wireless domain boundaries. Some implementations employ proximity/boundary detection to enhance handoff triggers, which initiate handoff mechanisms between different networks, as an MMMD moves between wireless networks, via a wireless domain portal. Some implementations involve methods and devices for device validation and authorization. An MMMD is provided with local wireless network awareness, which may be used by the MMMD to have the appropriate radio turned on and properly tuned. Accordingly, the methods and devices of the present invention achieve power savings and improved handoff across networks.