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After a few years of relatively slow growth, mobile payment and ordering services have recently started to make a big push into UK restaurants. Wagamama, Gourmet Burger Kitchen, Wahaca and Hummus Bros all grabbed headlines in the first few months of the year, so we tested each of their app offerings – and learned a lot in the process.

For example, while paying and especially ordering a meal on your smartphone might seem designed to take the human element out of the restaurant experience, these systems actually put even more emphasis on the people. Purchasing something as physical as a steaming bowl of noodles using an app still feels slightly alien to most customers, so it’s vital that staff are fully trained and on-board with the process to make them feel comfortable.

The mobile technology supporting this experience is just a bridge, and as with any bridge, what matters is that the ride is smooth. After all, you don’t think about the technology behind your debit card, whether you’re paying contactlessly or using a PIN, until it doesn’t work. In the best examples we tested, paying on mobile felt routine – like it was just another option alongside cash or card.

Having a smart, well-designed app is a nice added bonus, but it's a secondary concern to ironing out the bumps for customers, and making the entire process as simple and quick as possible. With that in mind, let's take a look at what these four restaurants have to offer.

Gourmet Burger Kitchen

• Launched: March 2014


• Powered by: PayPal

While it was the restaurant's integration of PayPal that we tested out, it's also worth mentioning Gourmet Burger Kitchen's recently-released branded app.

Powered by FlyPay, also behind the Wahaca app reviewed below, the app offers mobile payment capabilities, and the option of ordering meals for takeaway, plus support for special offers and GBK's loyalty scheme. It's considerably more fleshed out, which is to be expected, as PayPal's app is designed to cater for a much wider range of businesses – in the 'Local' section, GBK sits alongside everything from small charities to individual people – so naturally the experience isn't as neatly tailored to a single use case in the way the branded app is.

This means that PayPal is left feeling a little bit like the poor relation. While GBK's own app was being promoted around the restaurant, PayPal had no presence in store and the staff didn't seem to be trained to use it. When we told the waitress, as instructed, “I'm paying with PayPal”, she presumed this meant through GBK's app and, as this was the first PayPal payment she'd ever taken, she was obliged to go off and find a manager.

PayPal lacks some of the bill management options of the other apps we tested, like adding a tip or splitting the cost, but it has a nice USP: the app only requires a photo of the customer for identification. This works well, eliminating the need to enter a long number into the phone, read it out to staff or scan a QR code – though in my case, this did lead to a little embarrassment, as the waitress laughed out loud when the scruffy selfie I'd snapped outside the restaurant suddenly popped up on her till screen.

Overall, PayPal had less of an impact on the restaurant's ordering and payment process than any of the alternatives else we tested, and seems to be a good, cost-effective way for restaurants to dip that first toe into the water of mobile payments, before they invest in a more bespoke solution. This is true not just of GBK, but also Nando's, Prezzo and Busaba Eathai, all of which have launched their own branded payment apps since partnering with PayPal.

Wagamama

• Launched: March 2015


• Powered by: Mastercard Qkr

Wagamama was the launch partner for MasterCard's mobile payment service when it came to the UK, and is currently the only restaurant chain in the country to have adopted it – but, firing up Qkr, you wouldn't know it. The restaurant doesn't receive top billing in the app, only appearing when you search for nearby locations.

This is understandable, given that MasterCard presumably wants to establish its own mobile payment brand rather than relying on its partners, but it might make adoption from Wagamama customers more difficult than if it was housed in a branded app.

Step into one of Wagamama's locations, however, and it's a very different story. The restaurant where we tested Qkr had banners, place mats and table tent decorations promoting the app. And while, speaking to our waitress, it didn't seem like there had been a flood of Qkr users through the door, the restaurant and staff were well-prepared to accept mobile payments.

It's worth noting that while Qkr does offer an in-app ordering process to restaurants, Wagamama is currently only taking advantage of its payment aspect. This means there is still some interaction with actual human staff required – bad news for misanthropes, but a good way to sidestep the problem of looking like you're running out on the bill.

Speaking of the bill, it is replaced with an order screen that gradually fills up with items as your orders reach the kitchen, with a running total updated in real time. This alone makes for a strangely compelling experience, and it's backed up by a robust payment functionality which makes it easy to split the bill and customise tips.

The one thing that will convince people to use Qkr, though, is simply the ability to get up and leave without having to wait for a member of staff to bring the bill. The waitress said the app seemed popular for business lunches, which makes perfect sense – and while it might not be the right fit for some restaurants, it's a neat complement to the casual shared-table style of dining that Wagamama offers.

Wahaca

• Launched: September 2014


• Powered by: FlyPay

Everything about the Wahaca app feels perfectly on-brand, from the real-time playlist of the music currently playing in your restaurant to the quirky loading messages. What really matters, though, is the payment process.

While there is no ability to order using the app, Flypay's payment functionality is impressively robust. The bill management feature in particular is comprehensive, making it possible to split the bill by individual items, or by percentage, if you're going Dutch. Either way, it neatly sidesteps that moment where everyone digs out a calculator app and goes quiet while they do their sums.

Multiple people can pay separately on one phone, and each set their own tip. To save on the fiddly entry of long card numbers, it's even possible to add a credit or debit card by scanning it with the phone's camera. It's a smart, fast solution that meant that, though we hadn't originally intended to, our whole group ended up paying with the app.

Vitally, the staff were well-prepared when we asked to pay with the app and our waiter even came over to confirm that the payment had been received. The Wahaca app does ask you to upload a photo, but doesn't use it for identification purposes à la PayPal. Instead, to connect the customer with the restaurant's EPOS, it requires you to enter the table number into the app. Not too difficult, given that these are one- or two-digit numbers, but Wahaca is also trialling QR codes in certain locations

The only slight issue with Wahaca's app is an inability to look back at previous orders in the app, presumably intended to keep the app simple and focused. However, like all the other apps we tested, it does use e-receipts, sent automatically to your email address once payment is complete. It's hard to pick any holes in Wahaca's payment offering, but it would be interesting to see if the restaurant could manage to integrate Flypay's ordering functionality this smoothly.

Hummus Bros

• Launched: February 2015


• Powered by: Judo

Hummus Bros is a small London-based chain with a focus on takeaway and quick lunches. Accordingly, its app is focused on placing pre-orders, then collecting a ready-prepared meal at a time of your choice – perfect if you've not got much time to spare or are doing an office-sized lunch order.

The Hummus Bros app is centred around a simple, streamlined menu screen. Dishes can be customised, by choosing a size or adding extra sides, and store locator and loyalty functions are neatly integrated. I ordered a meal to be picked up 30 minutes later, and paid by debit card, which was all perfectly simple.

The problem occurred when I arrived at the restaurant, reservation number and phone in hand, to find that my order had never reached them, despite the system processing it and automatically sending a confirmation email. This led to a staff member awkwardly reading my order off the phone screen, explaining that the branch was encountering problems with its back-end systems.

It’s possible that this was a one-off case of technical issues, but if the order had been larger or the store had been busier, this could be a real issue and, at the very least, it defeated the object of pre-ordering on mobile in the first place.

If your average customer, trying out mobile ordering for the first time, hit this kind of bump in the road, it’s unlikely to matter what caused the problem, or whether it's likely to happen again. It probably just means that they’re put off using the app again – or worse, that they’re dissuaded from trying a different restaurant’s app in future.