If you are travelling for the holidays, be prepared – the chance of your flight being delayed or cancelled is higher than usual. Recent mergers, such as of United and Continental in 2010, and British Airways and Iberia in 2011, have led airlines to reduce service in North America and Europe, combining formerly overlapping routes to cut costs (and hike fares in the newfound absence of competition), resulting in fuller planes and fewer alternatives should something go wrong. In particular, only 14% of seats on average are expected to be empty on US flights over the next few weeks, so if you do find yourself stranded, it may be even harder than usual to get re-booked on a new flight.

Add in the unpredictability of winter storms and you have the potential for what Germans call “Winterchaos”. Just think back to February 2011 when icy conditions in North America led to the grounding of about 20,000 flights, according to FlightAware.com, or December 2010, when snowstorms in Europe and the US led to about 8,000 flight cancellations.

As such, it’s useful to know what your rights are – especially when it comes to reimbursement for additional costs or compensation for the hassle – and two apps give the lowdown: FlyersRights.org covers flights originating at US airports for domestic and international routes and Your Passenger Rights is its European counterpart, though there is overlapping coverage in cases of transcontinental flights between the US and Europe.

Helpfully, you will only need to downloaded these apps once. If government rules change, the apps will update themselves, so you’ll always the latest information on hand.

Flying from the US
First created by the private US lobbying group FlyersRights.org in 2010, and routinely updated since then, the Flyers Rights app makes it easy to find out what reimbursement you are entitled to for costs incurred in a variety of flight-related complications. For example, in April 2010, the US government ruled that planes can only sit on the tarmac for a maximum of three hours for domestic flights and four hours for international flights before they must either take off or return to the gate. If you’re trapped on a plane that suffers from such an extended tarmac delay, the app explains what meals and calls you are entitled to and how to ask the airline to get what you’re owed. The app also lets you record your delays in real time, using a built-in GPS system and map for evidence, and tells you how to file a complaint with the US Department of Transportation if the airline ignores you or denies misbehaviour.  The app, which works for the iPhone/iPad, costs $0.99.

Flying from Europe
Launched in July 2012 by the European Commission, the Your Passenger Rights app lists the facts straight from the lawmakers themselves. It even takes into account the latest changes to compensation statutes.

For example, in October 2012, the European Court of Justice ruled in favour of a new regulation that gives passengers the right to claim a payout whenever the airline is to blame for a flight arriving at a destination more than three hours late. Flyers may ask for between 250 and 600 euro, depending on the length of the delay and the scheduled flight time, in addition to free meals and telephone calls.

There is fine print, of course, but that’s why the app is really helpful. Whether your flight is delayed or cancelled, bags are lost or you’ve been bumped involuntarily from an oversold flight, the app helps you weed through that fine print to determine what your rights are and how to insist on compensation.

The app, which also covers rail travel rights within Europe, is free for Apple, Android, Blackberry and Windows devices.

For advice on how to approach an airline representative once you know what you’re owed, read our tips on getting compensation when a trip goes wrong.

Sean O’Neill is the travel tech columnist for BBC Travel