John Lewis has announced plans to invest £4m in a new customer service initiative in 20 of its shops to strengthen its omni-channel customer experience. The investment will see 8,000 Partners who work on the shop floor, receive an iPhone loaded with a dedicated 'Partner App' designed to enable them to quickly help customers with information about products, check stock availability, and place orders. This development will put an end to customers waiting for Partners to go to stock rooms to see whether a product is in stock, or check information at tills as they will be able to help on the spot.

The app was designed and built by John Lewis's in-house online team using feedback from Partners in its Cambridge shop where the project was tested with customers for five months. Following a training programme this summer the mobile phones will be rolled out to the 8000 shopfloor Partners in 20 John Lewis shops across the UK.

The app gives Partners visibility of stock availability in all shops and at John Lewis's warehouse in Milton Keynes, where online orders are fulfilled, as well as product information, customer reviews, the ability to email customers product information and to place orders. During the busiest week in the trial, half of all online purchases made in the shop assisted by a Partner were made using the app.

Announcing the new initiative Craig Inglis, John Lewis's customer director, says: "As online and physical worlds increasingly come together, this initiative, which forms the foundation of our digital strategy for shops, will support our Partners in offering great customer service in a digital world.

"During the trial in our Cambridge store, customer feedback was overwhelmingly positive. It consistently speeded up response times to customer queries as Partners didn't need to leave the customer to find answers, or complete a purchase. This is just the beginning. We will keep adding to the Partner App in the future with new, innovative ways to help our customers."

John Lewis first started to bring its online business into its shops in 2008 when it installed screens so that customers could look up product information and check online availability. Earlier this year the retailer ​introduced a self check-in option at  its collection desks in shops. Customers wanting to use this put their order number into an iPad while they are queuing, and the Partner serving them will greet them with their order, so speeding up the process.