DISCLAIMER: This is my opinion and is not legal advice. Consult an attorney for legal advice.
Short answer:
Don't bother looking for or patenting your stuff - it isn't worth it on either side of the equation.
Long answer:
A couple of lessons that I've learned along the years as an engineer building software stuff, with 30 patents to show for it:
a) You're better off not looking for patents you may be infringing - if you happen upon something now and use it later, that's willful infringement. Willful infringement = treble (3X) damages; accidentally infringing is better. [This was the advice of our IP counsel.]
b) Given that you're not intending to infringe on someone else's patents, just build what you think you need. It is the patent owner's problem to PROVE that you are infringing. They can start with a C&D, they can start by requesting licensing fees, or they can start by suing you, but it's always their move first.
c) Shipping your product gives you right-to-use if you shipped your product prior to the priority date of the patent, and can also be used as prior art to blow up a patent if someone asserts it against you.
d) Finally, since you're building software, you can always design around the patents if they don't represent a fundamental aspect of your application.
As for patenting your own stuff, it's a really ***** expensive proposition. If you have something where you believe you can gain a business advantage greater than the $5K you'll need to put into the initial patent application, the 5 year wait for your application to ultimately be rejected, and the fight with the patent office and more $'s for that fight, then start by hiring a competent patent attorney to write up your application.
Having patents is cool, but it's not necessarily a money-making endeavor. And everything I said above about you as the potential infringer applies equally to you as the potential infringee - you have to PROVE that the alleged infringing product infringes one of your claims.
Bottom line: unless you've got something that other people will want to pay money for OR that you can use to keep your competitors out, don't bother with patents.
