Considerate isn't a word we'd use to describe many people's behaviour on public transport. And with everyone's eyes glued to their screens during transit these days, it can even be difficult for pregnant women – and others less able to stand – to get a seat. Enter Babee on Board, an app that launches today, which aims to help pregnant women get a seat on public transport. It consists of two apps which communicate via Bluetooth, the BBC reported . The person hoping to sit down sends an alert via their app and anyone nearby with the app will receive a notification saying someone needs to sit down. The app with the alert button costs £3.99, which developers said was to stop it from being used by trolls messing around. The profits will reportedly be donated to a children's charity. The partner app that notifies passengers is free to download. Hew Leith, chief executive of 10X, the British creative agency which created the app, said: "We would rather give it away for free but we need to ensure there's a barrier so people don't download it for free and troll those around them." The apps work together "like walkie-talkies" and require bluetooth location services and notifications to be enabled. Currently only Apple users can download it, reported the BBC. "We should be using our eyes [instead] but if you look around you, everyone whips out their phone as soon as they sit down," Leith said. When the developers tested out the app, many women said they most needed a seat early on in pregnancy when they weren't showing but felt most ill. Fellow passengers can't always see women's "Baby on Board" badges either, Leith added. The National Childbirth Trust (NCT) welcomed the app, with its senior policy adviser Elizabeth Duff saying anything that helps pregnant women "to have a more comfortable journey can only be a good thing".