ServiceDesk Professional has power packed features to get full control of your service data and streamline your service management. It has advance features such as

Complaint management register, assign & close.
Re-assign complaints.
Contract management.
Contract renewals along with the history.
Schedule Service.
Manage Quotations with item wise tax & multiple terms.
Manage Customer Contacts.
Manage Brands.
Print options for service slip, complaint acknowledgement & contracts.
Analytics like dashboard & MIS.
Smart reports with excel export.
Excel upload to import legacy or external data into ServiceDesk.
SMS & Email notification to technician.
Access control.

It is a windows application with an option to store data On-Premise or Online (Cloud). The On-Premise version works without internet. You can store unlimited data without any restriction.