The BBC and ITV's offerings aren't the only official broadcaster apps to offer something along these lines. The Sky Go app allows Sky subscribers to watch up to 32 live channels, depending on their subscription. All the Sky Sports channels are available, along with Sky Movies and Sky's own other channels, including Sky1 and Sky Atlantic.
You don't have to be a Sky home subscriber to get these channels, though - Sky Go subscriptions are available without you having to get a satellite installed, so anyone can use the app. Just like TVCatchup, it works over Wi-Fi or 3G/4G, so you can get your fix anywhere.
Virgin Media TV customers with the latest TiVo box can also watch over 20 channels of live TV using the Virgin TV Anywhere app. Not only can you watch the channels live, but you also still have access to the TiVo box's clever recommendations and ratings systems. Unfortunately, it currently only works over Wi-Fi, so you'll need to be somewhere with a solid local network for it to work - you won't be able to catch up at the bus stop.
TV on demand
In just a few years, the way we think about watching shows has changed a lot. Starting with DVD box sets, it became normal (and completely acceptable) to devour whole television series in a matter of days - and that torch has now been passed to on-demand services, letting you watch whatever you want, whenever you want at a pace that suits you.
There are a ton of them available, but one of the pioneers was the BBC with its brilliant iPlayer service. The app lets you browse through a featured list of recent shows, or to search or go through them by category to find what you're after. It's also unusual in allowing you to download shows to your iPad for watching when there's no internet connection - all the other services here require you to be online.
ITV Player, Channel 4's 4oD app and Channel 5's Demand 5 all let you catch up with shows from their respective networks, and 4oD offers a good range of older shows as well. All of these apps are free to use, but what's available on them isn't always totally comprehensive - there may be shows that you can't watch.
The Sky Go app gives Sky subscribers access to its on-demand library, which includes many shows that are exclusive to Sky1 or Sky Atlantic, as well as productions from Sky Arts and some sports highlights.
LOVEFiLM and Netflix are the two big paid-for on-demand services. In both cases, you pay a monthly fee and can watch as many shows as you want, as often as you want, across multiple devices, which works out as a really rather good deal.
Both services made their names offering films, but now offer plenty of television shows as well - Netflix is more expansive in this regard, though, offering multiple series of many shows. It's a much more comprehensive service in America, but in the UK it still offers a great choice of television. LOVEFiLM isn't quite as wide-ranging, but is expanding in this area.
They cost similar amounts (approximately £5 per month) for streaming on-demand shows, so there's not much to choose between them on that front. Netflix is more TV focussed, with an easier-to-use interface and better recommendations, though.
Both services can remember your place in a show across devices, so it's super-useful if you start watching on your computer and have to stop, because then all you have to do is simply pick up where you left off on the iPad or vice versa, if that happens to be the case. Needless to say, we're big fans of both services.