how can i link the website and app together???

been thinking about what tammy said that how can people link the app and the website together???

WEEEEEELLLLLLLLLLLL... I dunno right now some ideas...

they can register online to recieve notifications to their phones about what is "hot" and stuff which will then have a little reminder that says "why not download our free app!?" or something like that!? and if they already have got the app then they can save things to the website so they can save things on their iphone which will allow them to go online and view them in a bigger scale etc. and they can get gifts etc! for example "winners can download the latest pattern to create a gorgeous summer dress online now" or something like that?!