In an attempt to spur user growth, Snap’s chief executive, Evan Spiegel, announced that Snapchat would be redesigned to make it easier to use.
The Unsend function is expected to work on all types of messages, including text, images, videos, GIFs and documents.
The company said an update would "integrate missing features".
As the iPhone took shape, its designers found themselves torn between making a phone or a computer.
New 5.5in smartphone might be bulky, but its super-shiny back and pressure sensitive controls make up for it
Promo images released show people using various filters including flower crowns and bunny ears.
When you are snapping with the rear-facing camera, just tap the camera screen to find the new lenses.