We have written what I anticipate to be a fairly popular mobile app in the DIY mechanic category. We are in the alpha implementation/testing phase for google play, and discovered the name we chose for the app is the same as a drilling rig parts manufacturing company located in Texas. Aside from the domain name also being owned by that company (doesn't really matter to us), we are concerned with Trade Mark law.
The mobile app we are developing already has a large marketing channel with a certain amount of anticipated downloads immediate. We could change the name slightly (adding even one letter). Is this even necessary (or effective?) given that this company has no reason to develop a mobile app for public use, and is in a completely different state and industry?
More specifically, the scenario we are concerned with: Our app quickly gains popularity, google search results for the name bring up our app primarily (not the manufacturing company) - this WILL likely happen immediately. Manufacturing company notices and sues us for trade mark infringement?