Adelaide's bike share scheme has been running since 2005, and offers 200 bikes at 19 different nodes. The scheme currently operates only in the CBD, North Adelaide and local government areas of Charles Sturt and Port Adelaide Enfield (western suburbs).

The service is free, but requires bikes to be picked up and dropped off at the same point, and those points are staffed locations:
 

www.bikesa.asn.au/adelaidefreebikes

In other cities, bike sharing is city wide and managed through use of electronic cards, allowing people to collect a bike at one point, and leave it at their destination. There are also systems which can track the availability of bikes in real time at each of the stations.

'Dockless' bike sharing schemes have recently emerged, which use GPS technology fitted to bikes, accessed via a smartphone app to locate, unlock and pay for use of the bike, eliminating the need for docks or nodes where people need to rent bikes.

Resources

Bike Sharing Feasibility Study for Adelaide
www.sensibletransport.org.au/project/bike-share-feasibility-study-for-adelaide/
www.sensibletransport.org.au/wp-content/uploads/2016/09/Bike-share-options-for-Adelaide-Stage-3-17.08.16v2LR.pdf

International Examples

London Bike Share Map
www.bikes.oobrien.com/london/#zoom=14&lon=-0.0853&lat=51.5116

Milan's Electric Bikes
www.cities-today.com/milan-adds-1000-e-bikes-to-bike-share-system