I suggest that you take the agreement to an employment law attorney in your state for an opinion of just how well it will hold up. In general, what the courts try to do when analyzing a contract is determine what the parties intended when then entered into it. Since the business of providing enterprise mobile platforms is apparently nothing close to what your employer does that makes that part of the contract unclear — surely that is not what the two parties meant. The question then becomes what did they really mean? Perhaps some other part of the contract will make that clear. Or perhaps extrinsic evidence (evidence outside the terms of the contract itself) would make that clear. The employer is likely going to be the one that has to put up a stronger showing here to convince the court there is a good contract and that your next employment is barred by that contract because in most states contracts to compete are disfavored so the court might not give the employer much leeway.