Apple WWDC 2016: iMessage receives huge upgrade with iOS 10, as it looks to take on Snapchat, WhatsApp and Facebook

New features for the previously relatively conservative chat app include ‘disappearing ink’ and huge emoji

Apple’s messaging app is getting a huge upgrade to take on its competitors in the upcoming chat wars.

iMessage will receive new features including disappearing ink messages and fireworks that take up the full screen. Its messaging app had previously been relatively conservative – avoiding the kinds of fun features that are found in apps like Snapchat.

But the new features rely heavily on emoji and visual effects, and appear to be aimed at making the app take on tools like Facebook Messenger and WhatsApp, as well as Snapchat.

Users will be able to replace words with emoji in a single tap, and send handwritten notes, while special "invisible ink" messages will appear when the screen is swiped, and animations can be added to a conversation that fill the entire screen.

The app has also been opened to developers for the first time so it can be used to complete financial transactions and other tasks. People will be able to send money through a message, for example – though only through external apps rather than Apple Pay, as some had expected.

The announcement came as part of Apple’s WWDC presentation – the annual event where it shows off upgrades to its operating systems and software.

As part of the update to Apple's desktop computer software, OS X was renamed macOS, with this year's version named Sierra after the mountain range that spans California and Nevada.

Siri, Apple's voice-based virtual assistant, has been added to the Mac for the first time, as has the ability to pay using Apple Pay. An option to use the payment service will appear on websites, with confirmation requests sent to a user's phone, where they can use their fingerprint to authorise them.

Mac users will also be able to use their Apple Watch to unlock a Mac when in close proximity to their laptop.

Apple Music, the subscription-based streaming service launched at WWDC last year, was also given a redesign after many reported the app to be too confusing to use. A user's existing music library has been pushed to the front of the app, with more playlist suggestions being offered by Apple.

All the updates showcased are being made available to developers this week, ahead of free upgrades for all Apple customers in the autumn.

Mr Cook took time out at the beginning of the presentation to pay tribute to the victims of the Orlando shootings, telling the auditorium that Apple offered its "deepest condolences to everyone whose lives were touched by the violence", before leading a moment's silence in tribute.

Additional reporting by agencies