Since SOTI Snap is a fairly new product, we are always looking for constant feedback to add new features to it.
TimePicker field is not currently available and the workaround for that will be using a text box as you mentioned. I can understand sorting custom time entered by users in different formats will be difficult and time consuming but that is the only option at the moment.
I would recommend that you should create a case with SOTI Technical Support here and have a feature request added for this feature to be included in the product. If you already have an open case, please feel free to mention it to the technical support representative and they will be happy to create a feature request for you.
Please let me know if you have any questions.
Technical Support | SOTI Inc. |1.905.624.9828 | firstname.lastname@example.org | soti.net |