It's the start of the holiday season proper as the schools close down and the holiday resorts fill up. Sun, sea and sand, but in the modern era, rarely a postcard. Well, you can do something about that with the Postcards app for Android and iPhone.It's a free download, allowing you to take a snap of your holiday, then send it to eCards, who will send it out as a good old-fashioned postcard. All you have to do is choose the right snap, add some text via your smartphone and your postcard is on its way to friends or family.Downside? Well, the app is free, but sending the postcards isn't. It costs 99p to send out a postcard second class, £1.49 first class, with payments via PayPal. If you happen to be in one of the far corners of the world, there's likely to be some data costs too.But if you happen to be simply sunning yourself in Blackpool or Brighton, it's a fairly small price to pay for impressing your friends with a tasty shot of you, a pint of lager and an overcast sky. To get the app, just search for 'postcards' in the Apple app store or the Android market.