Apple has recruited a beloved and surprisingly tech-savvy celebrity in its latest ad to showcase the new iPhone 6s "Hey Siri" feature. The minute-long ad titled "Timer" features the Cookie Monster using the always-on "Hey Siri" feature to set a timer as he bakes some cookies.

After popping a tray of cookies in the oven, the sugar-crazed Muppet sets the timer to 14 minutes, but quickly becomes impatient and calls on Apple's digital assistant, Siri, to cue up his "waiting playlist". Siri obliges and plays Jim Croce's nostalgic 1973 ballad Time In A Bottle, while the Cookie Monster playfully kills time with some silly, yet adorable behaviour, from playing with kitchen utensils to putting on a puppet show with oven mitts.

The commercial ends with the impatient Cookie Monster asking Siri for a status update on the timer only to find out that just 51 seconds have gone by.

The commercial highlights the new hands-free capability of Siri on the iPhone 6s, which is convenient and user-friendly. Although the hands-free "Hey Siri" functionality exists on all iPhones, older devices need to be connected to a power source to use it. Apple's latest handsets, the iPhone 6s and iPhone 6s Plus, can use it wirelessly.

With sales of the iPhone decreasing, the Cupertino-headquartered tech giant recruiting a decades-old, adorable star like the Cookie Monster might be the touch of honest, child-like charm the company needs in a celebrity endorser.

The Sesame Street Muppet is the latest in a long line of A-list celebrity talent recruited by Apple for its recent ad campaigns, including Jamie Foxx, Selena Gomez, Stevie Wonder and Steph Curry.

Apple is expected to announce a new, smaller iPhone called the iPhone SE, along with a 9.7in version of the iPad Pro and a new iPad mini at its upcoming press event on 21 March.