Could someone explain to me how companies are suppose to avoid infringing on patents?

With a device as complicated as a smartphone it's inevitable that someone holds the patents for numerous parts of the device and the software.

Is there a lawyer that is supposed to check out every single aspect of a device and check for prior patents? If so, then shouldn't the lawyer be responsible in this instance?

Note: I personally don't care if Apple loses patent cases, they've done enough damage with their own frivolous patent lawsuits.