The well known perceived future business model is constant (mobile) targeted (user profiling) advertising (everywhere) with instant purchase (online + mobile) and delivery (streaming)
So Apple (Android) + Facebook + Google + Amazon + (Netflix?) , right?
I think there's more to think about: the infrastructure is the gold; Hardware Manufacturers (CPU + RAM + SSD), Servers, Routers, ISP's, Content Producers, Transaction Processing, Data and User Platforms.
The new ecosystem is inherently more distributed (more users globally, more devices) and fragmented (more OS, Apps, Content Producers, etc.) than the "Microsoft Era".
Complexity increases with more data to aggregate/index/filter and many smaller transactions: consider previously purchasing a single desktop, monitor, (Windows bundled with it) and MS Word + one or two apps (Quickbooks or Photoshop).
Now it's a laptop + phone + tablet (Windows + Android + iOS), each with many apps (including online services like Facebook) and the challenge of maintaining a consistent view of security, data, and even application state.
Business purchases used to be larger, even grouped for volume (i.e. a company orders 1,000 desktops + monitors at $1,500 a piece); now it's bring your own device ($500) and many small app and content purchases for 99 cents to $10.
Companies that solve the multi platform and scalability problems (along with of course actually creating a product that fulfills a need or desire) will get bigger faster.
The opportunities are growing exponentially (network effect) for the talented, hard working teams that can execute.