The Subtleties of User Experience

As I'm sure most of you know, Wildtwig is protected by an OTP (One Time Password/PIN) authorisation system. To be able to buy iTunes vouchers from us you need to provide us with a South African cellphone number and we send you an OTP. If you've purchased from us before, either by successfully following the OTP process or by being a long time customer of ours from before the OTP days, you can also complete the OTP process via email.

We adopted this mechanism so that we don't require any of our customers to create an account. Account creation was a tedious process for all involved because we had to manually approve the account which often took time, thereby delaying the ability to purchase vouchers. Wildtwig has always prided itself on instant code delivery and having to wait for your account to be approved hindered that goal. With the OTP system we can offer instant delivery even if you've never bought from us before. It seemed the perfect solution.

Unfortunately our cellular providers in South Africa are not 100% reliable when it comes to automatic SMS delivery. Sometimes SMSs come through hours after they're necessary and other times they just don't come through at all. For us to offer a reliable service we had to solve this problem. Luckily voice calls over our networks are far more reliable. We utilise Twilio to make a voice call to the provided cellphone number, as well as to send the original SMS. Once we'd implemented the voice call option for when your SMS did not come through we thought we'd solved the problem but after watching our server logs and responding to our live support chats we realised that people were just not seeing the voice call link. So we made it more obvious: it got bigger and brighter but people still never saw it. So we added some motion by introducing a countdown timer that would draw attention to the link as well as provide an indication of how long you should wait before assuming your SMS would not arrive. Some days we still receive a live support chat about an SMS not coming through. We've assumed it's because people don't believe in the voice call link. I assure you it works. You won't have to wait for one of us humans to call you; our system will phone you immediately to give you your OTP. If you happen to have doubted the link in the past rest assured that it works and we want you to use it if you don't receive an SMS. It just goes to show that any assumption about user behaviour needs to be validated.

Overall we feel the SMS based OTP system has had a positive effect for our customers. They no longer need to sign up and remember a password and they no longer need to fill out applications and wait. Sometimes though, people don't behave as we expect them to and it's our fault for not predicting this better. We will continuously strive to improve your experience on our site and I'd like to invite you to make use of our live support chat if our service isn't perfect. Your happiness and satisfaction as a customer is our ultimate goal.


Robert Fall
Robert Fall

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