Apps (& games) are most people's experience of mobile - stats from Flurry show that apps now make up 86% of the time spent on mobile, and the mobile web just 14%.
The experience with apps used to be that you would open one, do something, and then open another one.
As time has gone on it's become possible to deep-link into apps.
My favourite example of this is CityMapper, the app that has done so much to demystify public transport (buses especially) in London for people like me,
The button below, if you open it up on a mobile, in CityMapper will direct you to my office. No need to open the app, and put the address in, this link takes to to precise instructions to get to 10 Triton Street, NW1.
While this is deep linking into an app from the web (which YouTube has been doing for years), we're now starting to see examples of deep linking to a precise place in an app, from another app.
Uber is a leader in this. Their recent API announcement unveiled a number of integrations -
"Here are just a few examples of how our partner apps are making it even easier to get where you want to go with Uber:
Dinner date? Request an Uber to your favorite restaurant right from the OpenTable app. Your driver will arrive already knowing where you are headed.
Catching a flight? The United mobile app shows ETAs of the closest drivers and fare estimates, so you can get reliable ride to and from the airport for less.
Night out? Time Out shows different Uber options—from low-cost to luxury—so you can be sure to arrive in style to the city’s best nightlife.
Need a place to stay? Book a room through the Hyatt Hotels & Resorts app and request a ride to your hotel right from the reservation screen.
Want a recap of your journey? Use Momento to view a timeline of your Uber trip history alongside other moments in your life."