In short
Larger, wilder and far less busy than its neighbour. The south, around Kuta Lombok, holds the surf and the beaches; the north, Mount Rinjani and its three-day climb.
The island is Muslim, which changes the atmosphere compared with Bali.
What it really costs
Rents are markedly below Bali, but long-term supply is thin and found mostly on the ground, not online.
A scooter is essential: the distances are large and there is virtually no public transport.
When to go
May to September, dry and windy. Rinjani closes in the rainy season, January to March, for safety reasons.
Crossings to the Gilis are cancelled in heavy seas, sometimes for several days running.
What nobody tells you
The region is seismic: the 2018 earthquake killed hundreds. You note where the exits are, as everywhere in the area.
The internet is the weak point: decent in Kuta, unreliable elsewhere. This is not an island for work that depends on video calls.