The Federal Aviation Administration has lifted a ban on most electronic gadgets on flights, even during parts of takeoff and landing. But passengers will still be banned from making voice calls on their cellphones.

Although the new rules are in effect, it may be a few months before fliers notice the difference. Individual airlines must first decide if they want to allow the expanded gadget use, then carry out a safety review to make sure gadget use will be OK on their aircraft.

The main electronic restriction will be that airlines can require passengers to either use airplane mode on their device, or use the in-flight wi-fi provided. Use of any cellular services, including voice calls, remains banned. The FAA didn’t cover the issue of cellphones in its review as they are subject to separate Federal Communications Commissions rules.

FAA chief Roger Huerta noted it isn’t practical to expect airline staff to check if individual users have switched on airline mode, but believes that issue will be solved by a combination of passenger goodwill and devices quickly draining their battery as they search in vain for a cell tower.

The biggest change is that in principle gadgets can now be used during the general takeoff and landing periods, with the FAA concluding there’s no serious evidence of risk to flight instrumentation. Previously gadget use was only allowed when the plane was above 10,000 feet.

Pilots will retain the right to ask for devices to be switched off in cases of landing in poor visibility, with the FAA estimating this will affect around one percent of flights.

Individual airlines may still restrict use based on physical safety. For example, they could insist that large laptops are stowed while the fasten seatbelts sign is on. It’s also likely that most airlines will insist that gadgets such as tablets and e-readers are put in the seat-back pocket for the couple of minutes when the plane is getting airborne or approaching the runway, the same policy that applies to physical books.

It’ll also be up to individual airlines whether and how they change their policies on carry-on bags.