A short introduction to the integration of payment gateways with websites and mobile applications


As their name implies, payment gateways serve as the entry point for the exchange of financial data with underlying banks or payment processors. In order to safely exchange financial data with banks and post ledger entries on each individual bank account, Payment Gateways are equipped with the information security standards that are required by authorities.




During the COVID-19 epidemic period, digital transformation and adoption have advanced dramatically. The offline retail industry has been negatively impacted by social distance standards, which have also put a pressure on cash flows and working capital. On the other hand, the coronavirus outbreak is affecting how consumers make payments. The majority of customers around the world were using digital payments more frequently than they had been before the epidemic, and they want to do so even once the virus has been contained.


Use case for thorough explanations


Let's say a business (merchant) wishes to accept digital payments online using a Paywise on their website or mobile application. The paper breaks down the six steps of payments enablement into frontend and backend processes to emphasize the required tech integrations.

Step 1 : Choose the products/services and proceed to pay


The user adds goods or services to the shopping cart on the merchant's website and wants to start a payment transaction for the whole amount in the cart.


Step 2 : Payment authorization and payment authentification

  • Authorization: The user is forwarded to a Paywise-controlled payments page where he or she will be prompted to choose a payment method—such as a credit card, etc.—and the fields required to enter credentials for the transaction will be displayed.

  • Authentification: The user is taken to the Authentication stage after the transaction has been successfully authorized. Here, the user must provide an OTP or a 3D Secure transaction password to verify the card transaction. At the page managed by the bank, this process is taking place.

Step 3 : Redirection to the page marking the completion of a transaction


Once the transaction has been completed, Bank/Paywise will call the merchant channel (website or app) and provide the transaction's final status. The status of a call-back transaction can be one of success, failure, or in-progress.


The returned data can then be used by the merchant application to display information about the completed transaction, such as the Order ID, timestamp, payment amount, transaction status, etc.


Step 4 : Server-2-server calls


This is a full backend process step that is initiated after the user has successfully completed a payment transaction. Paywise calls the Merchant server in this S2S response call. For security purposes, this API call has to have an API Key or encryption signature.


Why is it necessary to do this step after the user has finished the transaction?

  • By recording all of the data given by Paywise against the Order ID created in the merchant's database, this step closes loopholes in the transaction.

  • Typically, the business benefit (i.e., the good or service for which the payment is made) is only transferred to the client following successful S2S response from Paywise.


Step 5 : “Order Status API” and Polling Scheduler


This whole backend procedure is here. In order to use a "Order Status API," a merchant must provide the MID and Order ID as request parameters. Paywise will then share the S2S response in return. Following receipt of the response, the procedures outlined in "S2S Response" should be carried out.


Step 6 : Refunds


Only transactions with the "success" S2S response status from Paywise are eligible for refund processing. Only transactions with a "success" status S2S response can activate this backend processing (we cannot issue a refund if the funds have not been received).



Contact Paywise today and let’s have a chat about your e-commerce online payments.