An army of Oor Wullies disguised as astronauts, Lemmings, David Bowie and Marilyn Monroe have sprung up all over Dundee.

The 50 statues have been placed around many of the city's landmarks, including the Tay Road Bridge and Broughty Castle, as part of the Oor Wullie Bucket Trail charity initiative.

The official app is now available and members of the public can begin following the trail, collecting sculpture sightings on their travels and taking selfies along the way.

The artworks will be auctioned off at the end of the summer to raise money for the ARCHIE Foundation's Tayside Children's Hospital Appeal to create a new twin operating theatre paediatric surgical suite at Ninewells.

The ARCHIE Foundation, along with partners Wild In Art and DC Thomson, officially launched the Bucket Trail on Monday.

Some of the designs celebrate recent world events, including a Tim Peake-inspired Astro Wullie which will be outside Dundee Science Centre for the summer.

A David Bowie-inspired Oor Bowie commemorates the pop star, while others, such a Tunnock's teacake design, celebrate Scotland's heritage.

Members of the public have been taking part in the Oor Wullie Bucket Trail and there is also in interactive map.

Each sculpture has been sponsored by a business or organisation, with many local and national companies joining the Bucket Trail.

Cassie Thompson, head of fundraising for the ARCHIE Foundation, said: "As organisers, we are very proud and excited to see Oor Wullie's Bucket Trail arrive in Dundee.

"An incredible amount of work has gone into this project, which is all to help raise money for the ARCHIE Foundation's Tayside Children's Hospital Appeal.

"The support from the businesses and community organisations which have sponsored sculptures to the local schools who have embraced the project decorating their own miniature Oor Wullie sculptures has been amazing.

"This is a truly one-of-a-kind event that we expect will bring thousands of visitors to Dundee over the next ten weeks to explore the city, seek out the individual Oor Wullie sculptures spread across the area and pose for selfies on Oor Wullie's trusty bucket."

A group of Oor Wullie sculptures will also be taking part in a national tour in association with Scotrail.