A "low-cost" tablet that went on sale at the supermarket chain Aldi over the weekend has already sold out.
It comes after rival chain Tesco launched its own device, which has sold 300,000 units since it went on sale in September.
Both tablets have 7in (18cm) screens and use the Android operating system. Aldi's Medion Lifetab costs just under £80 while Tesco's Hudl sells for £119.
A spokesman for Aldi said the tablet was completely sold out in all stores.
"Specialbuy" promotions such as the one used to advertise the Lifetab were limited "only until stocks last", he added.
Both the Aldi and Tesco devices face competition from several 7in tablets already on the market including Google's Nexus 7 and Apple's iPad mini. These devices are more expensive, ranging from £199 to £350.
Argos also entered the market with its MyTablet, which launched in October.
Customers opting to buy the cheaper tablets available from the supermarkets would be looking for something different than those who bought the more expensive versions on offer from the likes of Google and Apple, said IDC's research director for mobile devices, Francisco Jeronimo.
"The biggest selling point here is definitely the price," he said. "Tablets are becoming very popular."
"The larger screen size gives entertainment on the move to users, which is becoming very popular among commuters and children.
"However, most parents don't want to spend £300-£500 on a device that will mainly be used to play games, to watch movies and a few other educational applications," he added.
Aldi's Lifetab has 8GB of built-in storage, and a 1.6GHz quad-core processor. In comparison, the Tesco Hudl has 16GB of built-in storage with a 1.5GHz quad-core processor.
The arrival of the Hudl, the Lifetab and the MyTablet are seen as important in gaining share of the tablet market in the run-up to Christmas.
Almost six million tablets were sold in the first half of 2013.
IDC estimates that 25% of tablets shipped to the UK between July and September were under £120 and it expects this to grow over the next few years.
While this is not seen as a move to position Aldi as a consumer electronics retailer, Tesco's tablet launch has allowed it to utilise services it already owns.
Tesco's Hudl tablet comes loaded with blinkbox, the company's movie-on-demand service. It bought blinkbox in 2011 in an attempt to gain a share of the growing online TV and video streaming market.