You've heard of Apple's Passbook, Google Wallet and maybe even Samsung Wallet (launched in Korea in May, soon to go global) but what about all the other digital wallet initiatives?
There seems to be a bit of frenzy when it comes to these developments, hardly surprising given the volume of transactions up for grabs, if (or should that be when) one or two of them become the wallet of choice.
SITA certainly has some interesting insight with Renaud Irminger, programme director at SITA Lab, predicting a mobile wallet war down the line at its Airline IT summit in June.
He points to initiatives from the above players as well as similar products from Microsoft Windows 8, planned launches from a number of mobile operators as well as payment specialists Mastercard and Visa.

"What's at stake is huge. All of those players are making strategic moves to capture your physical wallet and put it into the phone."
Where it all ends is anyone's guess but we might be mistaken for thinking, for example, that the popularity of a device will mean its wallet app wins through.
Irminger says if we take Apple as an example, which is going down its own proprietary technology route, and that doesn't allow (currently) for Near Field Communication (NFC) developments.
There are many that don't believe NFC is going to match up to the numbers predicted in recent studies (see this piece from Tnooz node Glenn Gruber) but the technology is being pushed by some mobile operators for security reasons.
Samsung on the other hand has announced a wallet that supports both NFC as part of secure element embedded in the phone and SIM-based NFC.
Aligned with this is the sort of point-of-sale technology being extended to retail outlets in different countries and related contactless payment cards including those from Visa (PayWave) and Mastercard (Paypass).
Worth noting that these initiatives are for small, every-day transactions currently.
Both payment giants have also developed digital wallets called V.me and Masterpass respectively.
Anyway, the point of all this is the billions of investment into digital wallets to replace our physical wallets and get a share of that mobile spend.
Where does that leave travel companies - having to hedge their bets with one or two dominant wallets or develop connections for all?
Which segues nicely into something else SITA has been working on - a boarding pass API.

Irminger says:
"Airlines today have been providing boarding passes via SMS or email or mobile applications. When Passbook was launched, some were quick to say 'this is good' and put it in, then you have Samsung wallet and Microsoft so, are airlines going to do all of those?
For airlines it has started to become difficult to be able to push a boarding pass to all these devices because each requires them to sign an agreement and a contract, making it fairly complex. It's very likely that one year from now an airline might be pushing a boarding pass to 10, 20 or even 30 types of wallets."
He adds that, when you add services such as What's App and social networks Facebook and Twitter to the mix, airlines might end up pushing boarding passes to them too in the name of passenger convenience.
Does it make sense for airlines to allocate scant resources to all these fragmented digital outlets?
SITA believes not with its API, which is live, and aims to offer one way for airlines to deliver boarding passes with the airline tech company taking care of the complexity.
It has already developed for Passbook and helped Malaysia Airlines develop code for the Samsung wallet.
Clip below with Irminger reinforcing some of the points from his presentation during the Air Transport IT Summit
Further details on SITA's 2013 Airline IT Trends Survey in this article.
NB: Soldiers image via Shutterstock