Those who subscribe to O2's mobile broadband service can now log on to all BT Openzone hotspots across the UK as well as 5,000 hotspots operated by The Cloud. BT Openzone is behind the public Wi-Fi networks in a range of hotels, airports and coffee shops, including Starbucks.
O2 has also announced an update to Connection Manager, the application mobile broadband subscribers use to connect to the web.
The tool now allows people to copy their laptop's existing Wi-Fi profiles during the software installation process. Also new is a data counter that allows customers to keep track of the amount of data they've downloaded, with notifications alerting them when they've reached 75 percent, 90 percent and 100 percent of their allowance.
Most customers have already received the Connection Manager upgrade. However, O2 said new customers will only get the new version of the software - and access to the additional BT Openzone hotspots - at the end of July.
BT Openzone also recently announced it is working with Cashbox - the supplier of ATM machines in the UK - to turn cash machines into Wi-Fi hotspots.
Cashbox named a number of its 2,500 sites across the UK that would become Wi-Fi hotspots, including ATMs located in the Tiger Tiger chain of bars, as well as a number of other London-based pubs and restaurants.
BT broadband customers with inclusive Wi-Fi minutes and O2 iPhone users will be among those that can use the Wi-Fit hotspots for free.