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#iOS integration

Setu provides ready to use URLs for iOS integration. Contact Setu to update your logo, colours, fonts as per your branding. You can reach out to for any further clarifications. This quickstart page provides the sample code for the following specs—

  • Programming language — Swift 5.* (Latest version 5.3)
  • Interface — Storyboard
  • Life Cycle delegation — UI Kit
  • iOS versions supported — 12+ (Latest version 14.4)

This quickstart provides the integration guidelines for iOS integration with Setu’s default UPI payment option. If you’d like to use your own payment gateway, please refer to this guide instead.

#Step 1 — Implement web view in your app

The following steps need to be taken for webview integration—

  1. Get link from the backend
  2. Open a webview and attach the iOS interface

Get link from the backend

This step gives a one time Setu URL to be used by your customer for the bill fetch or payment flow. The Create link API needs to be called when the iOS app wants to obtain a one time link to load Setu’s screen flow inside a webview.

None of the parameters aside from mobile number are mandatory, but depending on what is passed the returned link will display different UI.

You can have the following scenarios, depending on what you choose to send along with the customer’s mobile number—

  • If no other input is passed, it will take the user to the home page with all BBPS categories.
  • If category code is passed, it will show user a list of billers in that category.
  • If category code and biller ID is passed, it will show the bill fetch form where a customer can enter their identifers (biller specified parameters)
  • If the category code, biller ID and parameters are passed, it will show the bill directly.

All query parameters should be url-encoded to escape special characters

The above request will return URL based on the input params. Here’s a sample—

"link": ""

Switch control from your app to Setu

The link returned by the API should be loaded within WKWebView in a ViewController which implements UIViewController, and WKScriptMessageHandler. The controller must also extend and use a custom WKNavigationDelegate class to intercept and download PDF files.

If you’re using a cross platform solution—like Flutter, React Native, Ionic—look at the code snippets provided here.

The userContentController will need to implement one function—

  • unload — Used by the parent app to dismiss the webview
// The iOS observer function
func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
guard let dict = message.body as ? [String: AnyObject]
else {
let functionToPerform: String = dict["function"] as ? String ?? ""
switch functionToPerform {
case "unload": closeView()
default: break

The WKWebviewDownloadHelper which downloads our PDF file is used as below

override func viewDidLoad() {
let mimeTypes = [MimeType(type: "pdf", fileExtension: "pdf")]
helper = WKWebviewDownloadHelper(webView: webView, mimeTypes: mimeTypes, delegate: self)
webView.configuration.userContentController.add(self, name: "ios_observer")

WKWebviewDownloadHelper is dependent on the custom WKNavigationDelegate class

extension WebViewController: WKWebViewDownloadHelperDelegate {
func fileDownloadedAtURL(url: URL) {
DispatchQueue.main.async {
let activityVC = UIActivityViewController(activityItems: [url], applicationActivities: nil)
activityVC.popoverPresentationController?.sourceView = self.view
activityVC.popoverPresentationController?.sourceRect = self.view.frame
activityVC.popoverPresentationController?.barButtonItem = self.navigationItem.rightBarButtonItem
self.present(activityVC, animated: true, completion: nil)

#Step 2 — Optionally configure webhook

You may optionally want to listen to user events—like successful or failed bill fetch, bill payment status and more—through webhooks. Refer to this guide for more information.

#Step 3 — Get Production credentials and go live Once you are done testing your

integration, ensure that all KYC and legal agreements are submitted. Contact Setu for getting enabled on production.

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