Most relevant terms in mobile payments industry today.


Conversion rate

In this sense, a ratio of app users who became paying customers. Typically, mobile users download a free app that offers paid upgrades, expansions or additional content. if offered the right incentive, they will become paying customers, i.e convert into paying users.

Digital content

Movies, music, books, games or other types of content that is available only in digital form to be downloaded to and viewed or consumed on a computer, tablet or smartphone device.

Direct carrier billing / Direct mobile billing / Direct operator billing

A type of mobile payments where the purchase amount is charged to the mobile phone bill, or deducted from the prepaid balance. Typically, direct billing is used for micropayments for digital and virtual goods, but also public transport tickets or city parking.

In-app payments

Payments made within a mobile app and via an integrated payments system, either via direct mobile billing or a mobile wallet.


A financial transaction involving a very small sum of money, regardless of the object of purchase – virtual or digital goods, physical goods, ticketing or parking etc. Micropayments are usually made online and on mobile devices. The sum can range anywhere from 50 US cents to10 US dollars, depending on the criteria of the payment processor.

Mobile payments

Payments for goods or services made from or via a mobile device such as a mobile phone, smartphone or tablet. Mobile payments technologies vary in type and application. Some are restricted to point-of-sale transactions, while others are best suited for micropayments of up to $10. Some require bank accounts or credit cards, others do not. Some require smartphone apps to function, others work on feature phones. What all have in common is the fact that a mobile phone is required.


A number uniquely identifying a subscription in a GSM or a UMTS mobile network. An MSISDN is the phone number associated with a single SIM card, in other words, the MSISDN is the number you need to input in order to place a call or send an SMS message.


Also known as a mobile wallet, this is a digital equivalent to a physical wallet, an app containing digitized valuables such as credit or debit cards, loyalty program cards, public transport cards or other identification. Generally, mWallets are used to make different types of payments, either via NFC technology, or online (mobile and desktop), as well as collect loyalty card points and use benefits.

One-tap purchase

Purchase made on a smartphone with a single tap to confirm payment. Most commonly used to purchase virtual and digital goods in mobile apps (cf. In-app payments; however an in-app payment is not necessarily a one-tap payment).

Payment API

Application Programming Interface is a set of tools and protocols for building or integrating software applications. Centili’s payment API is used by developers and companies who want to integrate Centili mobile payments into their online or mobile application.

Premium SMS billing

This method of mobile payment relies on an SMS message charged at a premium price, usually equal to the value of the item purchased, sent by the mobile user to a specific number, and usually containing an item-specific keyword.

Scratch cards

A way of topping up a prepaid mobile account issued by a mobile operator. Scratch cards contain codes which are then entered in the Centili widget for topping up the Centili account or making a payment via Centili.

Trusted flow

One-click payments flow that requires no redirection to MNO’s page. Trusted service is provided by MNOs for those services that meet their proposed standards.

Virtual currency

A type of unregulated digital money which is issued and controlled by its developers, and used and accepted among the members of a specific virtual community (ECB definition, 2012). Essentially, virtual currency is purchased with real money in the real world and spend in the virtual world for virtual items. Example: coins in an online fantasy game, which can be earned in-game, or purchased in the game publisher’s store.

Virtual goods

Non-physical items within a social network or video game, such as stickers, game powerups, in-game or in-community currency.

WAP billing

A way for mobile users to buy content while browsing on mobile devices using the Wireless Application Protocol (WAP). For WAP billing to work, the mobile device must be connected to the mobile data network, but the consumer does not need to register or visit a specific page to complete the purchase. The amount will be charged to the charged to the mobile phone bill, or deducted from the prepaid balance.