View source for Brief survey of existing payment services

Debit payments are possible where an account is prefilled and drawn down for each transaction. The account could be your bank account, or it could be a separate account that you fill with you regular credit or debit card. Another approach aggregates your transactions subject to some overall limit and requires you to settle in full or in part at the end of the month.

''please add to this list and amend as appropriate''

* [http://www.westernunion.com/ Western Union] - person to person transfers settled online through a user's debit or credit card or through cash payments at Western Union outlets
* [http://linux-hosts-ltd.com/ Linux Hosts Ltd] - one of the very few UK hosting providers that accepts WU transfers in order to receive web hosting fees from new and existing customers. The company has clear instruction on its site on how to pay cash. An ideal solution for customers who are unable or unwilling to make use of credit cards, bank accounts or PayPal
* [http://linux-hosts-inc.com/ Linux Hosts Inc] - one of the very few web hosts in the US that accepts Western Union money transfers from its customers. The procedure is clearly indicated in the company's website. (Potential) customers with a frozen PayPal account or invalid credit card can benefit from this.
* [https://www.paypal.com/Paypal PayPal] - online payment service settled through a user's debit or credit card
* [https://www.paypal.com/webapps/mpp/credit-card-reader Paypal Here] - dongle converts phones into wireless card swipe reader for card payments
* [[Paypal Beacon]] - works with PayPal app on phones with Bluetooth Low energy (BLE) hardware
* [https://stripe.com/ Stripe] - online payment service settled through a user's debit or credit card. [https://stripe.com/blog/stripe-connect Stripe Connect] allows Stripe users to securely share their data with merchants. Examples include subscriptions, payment plans, coupons, discounts, invoices and disputed items.
* [http://www.allpay.net/ allpay] - offer services to pay bills online via the Web or native apps for iPhone, Android and Windows Phone. Swipe cards are available for cashless payments for meals and other items in schools.
* [http://www.tencent.com/en-us/ps/ecommerce.shtml Tenpay] - online payment service for individual and corporate users operated by [http://www.tencent.com/en-us/index.shtml Tencent].
* [https://squareup.com/ Square] - dongle converts phones and tablets into wireless card swipe reader for card payments, "Pay with square" - pay without even touching your phone, merchant automatically opens your tab as you walk in the door, and at checkout time, confirms your identity by your name and photo. ''How does the merchant sense your presence (WiFi, Bluetooth, GPS, explicit Web notification)?''
* [https://www.sailpay.com/ Verifone SAIL] - dongle converts phones and tablets into wireless card swipe reader for card payments
* [http://www.flintmo.com/how-it-works/ Flint] - use the phone's camera to read your debit or credit card, and enter card verification information
* [http://www.ecomcharge.com/ Payment Service Provider]-improved software development for the payment of goods over the Internet. Support all international payment cards and systems such as the One-stop shop solution and White label solution.
* [https://www.v.me/ V.me] - enter your email address and password at checkout as a proxy for swiping your Visa debit or credit card, in addition, support for NFC payments from your phone with the V.me account
* [http://www.mastercard.us/paypass.html Paypass] - NFC payment solution for Mastercard NFC enabled debit or credit cards, and now from your phone with the ''PayPass wallet'' 
* [http://weve.com/partners Weve] formerly known as Project Oscar - mobile wallet with payment via the mobile network or via NFC - joint venture between Vodafone, O2 and Everything Everywhere (parent company of T-Mobile and Orange in the UK)
* [http://www.paywithisis.com/ Isis] - mobile wallet with payment via NFC at any Isis Ready merchant.
* [http://www.mastercard.com/masterpass/ MasterPass] a mobile wallet from MasterCard, which allows consumers to keep all their payment and loyalty card details as well as shipping addresses on their phone. MasterCard says this will accept cards and payment systems from competitors. Websites will be able offer a MasterPass option for online payments. Stores will be able to offer QR Codes on items that customers can scan and pay for instantly.
* [http://www.google.com/wallet/ Google Wallet] - Credit and debit cards details are stored on Google servers and can be used from the phone or computer. Phones with Google Wallet and NFC hardware can be used for payments at PayPass enabled terminals. The wallet can be remotely disabled if the phone is lost or stolen. See also [https://developers.google.com/commerce/ Google Commerce APIs]. This includes support for hosted search through an online retailer's  inventory, as well as the means to give buyers the ability to authorize third party access to their Google Wallet payment credentials for streamlined purchase flow. The [https://developers.google.com/commerce/wallet/digital/docs/index Google Wallet for digital goods] is designed for micropayments for virtual goods. The [https://developers.google.com/checkout/ Google Checkout API] is being merged into the Google Wallet.
* [https://www.thelevelup.com/how-it-works LevelUp] - mobile display or printed card with QRCode as a proxy for the user's debit or credit card
* [http://oneapi.gsma.com/ GSMA OneAPI] - HTTP based network payment protocol aimed at mobile operators
* Contactless payment cards - these are conventional debit and credit cards that also include support for contactless payments under a given limit, see [http://www.theukcardsassociation.org.uk/wm_functions/fnc_get_document.asp?DocumentID=141&Filename=Contactless%20Cards%20The%20Facts%20v6.1%20EM_SH.pdf UK factsheet]. You just hold your card against the reader and don't have to type in a PIN. This has given rise to concerns about security, e.g. the ability to surreptitiously scan information. This is however, limited to the information printed on the card with the exception of the 3 digit security code on the back, i.e. the user name, the primary account number (PAN) and the issue and expiry dates. Users are protected against fraud, but banks are not liable for identity theft.
* [https://wiki.mozilla.org/WebAPI/WebPayment Mozilla WebPayment API] - introduced in [http://www.mozilla.org/en-GB/firefoxos/ FirefoxOS]  with initial support for Telefónica's Carrier Billing functionality, but with a view to future extension to other payment providers. The app initiates a payment by signing a request and calling navigator.mozPay(). The browser then displays a dialog for authenticating the user to the payment provider, and for the user to confirm or cancel the payment. The app is notified with a call back, and the app server is sent a signed POST request with a Payment Provider transaction identifier indicating that the purchase was completed successfully. See also [http://techcrunch.com/2013/04/04/mozilla-moves-ahead-with-its-plans-for-a-common-web-api-for-payments/ techcrunch article 4 Apr 2013]
* [https://www.facebook.com/payments_terms Facebook Payments] - allows users to pay for services using their local currency. A variety of payment options are supported including credit and debit cards, mobile carrier billing, and Facebook gift cards. Funds are transferred via the user's electronic value balance. 
* [http://developer.mintchipchallenge.com/index.php MintChip] - a stored value system backed by the Royal Canadian Mint and denominated in various currencies. It relies on a secure element, integrated within a smart card, SDCard or USB stick, that maintains the balance held, and uses the private key of the Mint to sign transactions. A random number is used to detect duplicates and avoid double spending. The MintChip is associated with a cloud based account to top up the card. For devices like the iPhone that don't support microSD cards or USB, MintChips can be remotely hosted by a trusted third party and accessed via HTTPS using either XML or JSON.
* [http://bitcoin.org/ Bitcoin] - a decentralized electronic cash system based upon cryptographic tokens with a peer to peer solution for managing anonymous transactions and minting tokens. Bitcoin is the first digital currency that avoids the need for trusted intermediaries to prevent double spending. This makes it hard to regulate, and Bitcoin has gained notoriety through its use for shady transactions. Arstechnica report: [http://arstechnica.com/tech-policy/2011/06/bitcoin-inside-the-encrypted-peer-to-peer-currency/ Bitcoin: inside the encrypted, peer-to-peer digital currency].
* [http://paymium.com/ Paymium Paytunia] — an open source wallet solution that processes payments in Euros over the Bitcoin network.
* [https://developer.amazon.com/help/faq.html?ref_=pe_132830_28130940#AmazonCoins Amazon Coins] — A virtual currency for in-app payments in the Amazon ecosystem.

Some more experimental approaches:

* [http://centup.org/ CentUp] - web pages add a button that transfers a few cents from a prefilled account, with 10% going to CentUp, and the rest split evenly between the web page publisher and the charity of the user's choosing. The charity and the amount transferred (default 20¢) is set in the user's account profile. The account needs to be prefilled with a minimum of $20.
* [http://flattr.com/ Flattr] - prepay service for making payments to sites displaying ''Flattr'' button, where your monthly spend is divided amongst the sites where you clicked the button
* [http://payswarm.com/ PaySwarm] - payment solution that splits payments across people listed in a PaySwarm digital contract. Supports decentralized identity and payment, in-app purchases, browser-based purchases, digital signatures for authentication/security, proof-of-purchases, offline purchases, micro-transactions, and crowd-funding. Payswarm forms the basis for [http://blog.meritora.com/ Meritoria].
* [http://www.webcredits.org/ WebCredits] - simple system for storing and transferring IOUs (credits) between agents
* [http://www.opentransact.org/ OpenTransact] - HTTP based payment protocol
* [http://www.ifex-project.org/ IFEX] - protocol designed to facilitate the negotiation of financial transactions between internet-based financial endpoints
* [http://ripple-project.org/ Ripple] - credit based solution where commitments to pay ("IOUs") are exchanged along trust chains
* [http://opentabs.net/ Opentabs] - credit based solution involving settlements of cryptographically signed open tabs ("IOUs")
* [http://dev.webinos.org/specifications/api/payment.html webinos payment API] from the [http://www.webinos.org/ webinos research project]. It is not linked to a specific payment service provider and is designed to be sufficiently generic to be mapable to various payment services like GSMA OneAPI, BlueVia, Android Payment API or PayPal.