There has been much speculation about the mobile phone as the all-in-one payment device of the future, and while adoption of that technology has taken off in Japan, it's still largely theoretical in most of the rest of the world.

Sweden is getting closer, though, with the announcement of a deal between payment providers Accumulate and PayEx.

The blog Arctic Startup is reporting that the technology is being tested in "selected stores" on the island of Gotland. Users register with PayEx, then link their account to a chosen bank account or credit card to enable the flow of funds. A client app is provided for the user's cell phone.

Arctic Startup gives a sample user flow for a purchase:

1. The buyer starts the PayEx client on the handset 2. The retailer enters the sum to the payment terminal and the buyer sweeps the handset/RFID item near the terminal 3. The transaction is shown on the customer's handset, and can be accepted by pressing OK (or the amount changed) and entering their personal code. Also credit can be used for part or whole of the purchase.