After two years in operation, a smartphone app designed to highlight flaws in Perth's cycling network has identified the city's most dangerous and neglected bike black spots.

Many of them are designated bike paths that end abruptly, sometimes without warning, or direct cyclists on to the road.

Others are paths that are cracked or covered with vegetation or sand.

The causeway bridge was at the top of the "most dangerous" list because its bike path is so narrow and is shared with pedestrians.

"This bike path was horrendous this morning," one rider wrote. "Lots of bikes, walkers, dogs, prams, joggers - it really is incapable of handling this traffic safely."

The app was launched two years ago by Greens senator Scott Ludlam. It allows cyclists to send photographs and descriptions of unsafe conditions to a website and to the WA Transport Minister.

Senator Ludlam said it was disappointing that so little had been done in the two years since the app was launched.

"The verdict is in - and the State and Federal governments have failed to do enough to look after the safety of WA bike riders," he said.

"Too much is being left to local governments to fill in the gaps."

One example of a path that ends abruptly was on West Swan Road in Caversham.

"It ends with no rationale and forces riders on to the road," one cyclist wrote.

The lack of facilities at the Perth Train Station topped the most neglected list.

"This poor girl (image on top right) had to carry her bike up the stairs," another wrote.

"We need rails that you can push your bike up.

"In Europe, they have rails built on to the stairs, just the width of a tyre, that you can pop your bike into and push it up.

"You still need to push it manually but at least you don't have to carry it. Hardly takes any extra room and very small cost."

Maintenance was required to the path on the western side of Brockway Road in Claremont.

A rider said there were two 500mm square depressions in the path that were dangerous to cyclists.

Transport Minister Dean Nalder said the Government was investing $47 million in cycling infrastructure over four years, including initiatives such as the Connecting Schools and Connecting Stations programs that provide a safe and sustainable cycling network linking schools and train stations.