Nextbike - public bike sharing system is available on several locations in the city. Bikes should be returned to any of their official locations. To get the code for the bike lock, you should call the number indicated on the bike, register and activate the account by transferring certain amount of money. Some of the locations are listed below, and the complete list is available on the official Nextbike web page:
Trg Kralja Tomislava (Main Train Station)
There are many taxi stands all over the city, and three major taxi operators: Eko Taxi (call number 1414, takes online orders), Taxi Cammeo (1212) and Radio Taxi (1777). The prices are similar. Starting price is around 10 HRK and taxi ride costs cca 5-6 HRK per kilometer. They will all have a taxi pick you up in just minutes after you give them a call.
Taxi drivers don't normally tend to rip off passengers, but there are exceptions so make sure that the taximeter is on.
Recently Uber has started operating in Zagreb. Their prices are similar to other taxi services for short distance trips but are much cheaper when going longer distance (e.g. to the airport).
Public transport system integrates tram, buses and rail. Some distant neighborhoods are connected with city buses, some with trains, but most of the city is covered by tram network. The public transport provider is named ZET (Zagreb Electric Trams).
The ticket price is 10 kn and it's worth for 90 minutes. You can buy it from the tram driver or at any news stand. The other option is to buy a "card" - it costs 10 kn and you can top it up with any amount you want. When entering the tram, just touch the yellow machine. Each ride will cost you 10 kn as well and this amount is valid for 90 minutes. There's also a possibility of buying a daily ticket (30 kn) or the ones that last longer that a day.
If you're staying in Zagreb for just a few days, it's a good idea to get the Zagreb Card since it includes free bus and tram rides.
Google Maps has recently integrated the tram system in their maps so you can use it to easily navigate with public transport.