There are so may ways Linked in can be of use to your business.
Recently, we have been working on a project for a client that sells and fits physical security, we've helped connect the client with relevant businesses such as buyers in the construction industry. We've then looked at ways of contacting those people directly, via InMail for one.
We also create relevant blog posts which we upload to their social media portals, when we have relevant stories to tell corralating between their business and any recent relevant news. Making for exciting reading, which can also help the Google ranking of their website and Linked In Profiles.
Don't be fooled by Linked In - think people aren't using it to it's full potential, so you don't need to either? Wrong!
That's the reason you should be using it to it's full potential! You can connect with relevant businesses directly that you're looking to attract, even if you don't directly get a sale immediately, it's still worth working on as it raises awareness of your brand. This potential client - might see your post on Facebook, LinkedIn and maybe they'll get something from you via email too... Leaving your businessed name in their mind when they need your service.
As you would expect, it's something you can get an app for, try too the app content builders, with images etc.