Mobile POS (MPOS) is a smartphone or tablet working as a card acceptance terminal, either paired with a small card reader or using the device's own NFC chip for contactless payments, so market traders, delivery drivers and restaurant servers can take cards without a countertop terminal. In the reader model, a PCI-approved Bluetooth reader encrypts card data before it reaches the phone, keeping the phone largely outside PCI DSS scope; reader-less SoftPOS runs under PCI MPoC, published in 2022. Readers often cost under €50, and providers usually charge a flat rate per transaction, suiting low-volume or seasonal sellers. Providers settling funds need payment institution or e-money authorization, or a licensed acquiring partner.
How does mPOS work
In the reader model, a pocket-sized PCI-approved card reader connects to the phone over Bluetooth. The customer inserts, taps or swipes a card on the reader, which encrypts the card data before it reaches the phone. The merchant's app sends the encrypted payload to the acquirer or payment facilitator, receives the authorization, and shows the result. The phone never sees readable card data, so it stays largely outside PCI DSS scope.
In the reader-less model, often called SoftPOS or tap to phone, the phone's own NFC antenna reads contactless cards and mobile wallets directly. Apple launched Tap to Pay on iPhone in 2022, and Android equivalents followed. PIN entry for higher-value payments is done on the phone's screen through a secured PIN pad in the app.
Security standards behind mPOS
Hardware readers are certified under PCI PTS POI. Reader-less acceptance runs under PCI MPoC (Mobile Payments on COTS), published in 2022 to replace the earlier SPoC and CPoC standards. MPoC covers app attestation, tamper detection and remote monitoring, because a consumer phone is not tamper-resistant the way a terminal is.
Mobile POS vs traditional POS
Hardware is the first difference: mPOS runs on a phone plus a small reader, or on the phone alone with SoftPOS, while traditional POS uses a dedicated countertop or portable terminal. Upfront cost follows from that. An mPOS reader often costs under €50 and SoftPOS can be free, against a few hundred euros or a monthly rental for a traditional terminal.
Pricing differs too. mPOS providers usually charge a flat rate per transaction, while traditional acquiring is priced as interchange-plus or blended, often with a monthly fee. That makes mPOS the better fit for low-volume, mobile or seasonal sellers, and traditional POS the cheaper option for high-volume retail and hospitality.
Flat pricing is simple but costs more at scale. At 1.75% flat, a merchant processing €30,000 a month pays €525; on interchange-plus at 0.9% all-in, the same volume costs €270 plus fixed fees.
Who provides mPOS
The category took off with Square's headphone-jack reader in 2010, followed by iZettle and SumUp in Europe. Most mPOS providers onboard small merchants as sub-merchants under an aggregation model: the provider holds the acquiring relationship and underwrites each merchant quickly, sometimes in minutes, which is why fraud controls sit mostly on the provider side.
Licensing angle
An mPOS provider that settles funds to merchants is usually handling third-party money and needs payment institution or e-money authorization, or a licensed acquiring partner. Buyers of such a business check whose licence and scheme membership the flow relies on, and how quickly merchant onboarding can be switched off if a partner leaves.