There are a few systems out there. Obviously there is ESRI's Arc Pad/ Arc Collector combo which will work off an android tablet. Trimble has terraflex which is a usefull data collection tool although dosnt save to a shape file (promised soon though). there Is Fulcum but i no nothing about it yet. Finally the Federated Archaeological Information Management Systems Project (FAIMS) which has a prototype android app for recording archaeological sites (but of course the database can be edited to reflect any other field recording) and this will be further developed in 2014 it promisses to be quite sophisticated.
Obviously this is a fairly general question as to be more specific we need to know your os; what you want to do with the data and more importantly $$$$ (especially when thinking of the ESRI products).
My view is that there is a gap between what is wanted and what is being provided. For me it is still too complected to collect data and have it sitting safely in my computer at home (the office) where I can use it. However I suspect that as more people look to make tablets more of a work device the situation will change.
I look forward to other responses to this question.