What does it do?

Excellent question! Perhaps this beautiful list of features will help you choose.

Key Functionality Pro+ Enterprise
Use on browser (PC, Mac, Smartphone and Tablet)
Online Support
Telephone Support
On-site Training
Asset Management Pro+ Enterprise
Asset Profiles
Access Profiles by Scanning QR Codes
Kits, Components and Assembly Profiles
Manage or Group by Models
Full Asset History
Asset Inspections
Warranty Information
Images
Purchase & Depreciation (Asset Register)
Contact Owner
Fault Reporting and Management
Group by Categories
Custom Model Personalities
Stock Level Management
Batch Updating / Import
Custom Asset Properties
iPad / iPhone (iOS) App
Inspections Pro+ Enterprise
Library of Common Inspections:
  LOLER
  PAT (manual and automatic from a number of popular testers)
  Visual Inspection
  Annual Service
  MOT
  Lamp Hours
Custom Inspections
Comprehensive Management and Reporting
Expiry by Date and/or Usage
Generate Certificates
Secure and Robust with Comprehensive Audit Trail
Batch Import Inspections
Run Inspection from Web Browser, Barcode Scanner or iOS App
Barcode Scanners (Separate Purchase) Pro+ Enterprise
Industrial Grade Scanners
Bluetooth Barcode Scanners (for iOS App)
Functionality:
  Pick or Dispatch Stock
  Return Stock
  Stock Count
  Inspections
  Custom Business Flows
Contact Management Pro+ Enterprise
Contacts
Grouped Contacts
Book Jobs against Contacts
Client Ledger
Document Management Pro+ Enterprise
Attach to Assets
Attach to Contacts
Integration Pro+ Enterprise
Export data in common formats
Batch Import optional
Import from PAT Testers
Email Inbox for Assets
Email Journaling
RESTful API
Job, Booking and Rental Management Pro+ Enterprise
Assign Labelled Assets to Jobs
Assign Parts and Non-Labelled Assets to Jobs
Assign Assemblies to Jobs
Assign Kits to Jobs
Assign People to Jobs
Basic Booking Types
Advanced Booking Types
Custom Booking Types
Comprehensive Job Rules Engine
Availability Checking
Alternatives
Accessories
Shortage Notifications
Pricing Engine
Pricing Engine - Advanced (Excel)
Integration with Xero
Sub-Hires
Cross Hires
Early Prep
Job Documents:
  Pick List
  Dispatch Notes
  Safety Certificates for Items on Job
  Invoice
  Carnet
  Crew Manifest
  Custom Documents Using MS Word Templates
Project Management Pro+ Enterprise
Sub Jobs
Timesheets
Crew Booking
Location Management Pro+ Enterprise
Locations
Sites
GPS Tracking
Reporting Pro+ Enterprise
Core Reports
Dashboard
Text, CSV, Excel, PDF, HTML Format
Custom Mail Merge Documents
Custom Reports
Reports(templates / market place)
Task Management Pro+ Enterprise
Assign to Contacts
Create from Asset
Create from Job
Assign to Groups
Auto-Creation from Report
User Management and Security Pro+ Enterprise
Activity Log
Manage by User Groups
Standard Security Profiles/Roles
Custom Security Profiles/Roles
Assign Permissions/Roles to User Groups
Notifications Pro+ Enterprise
Email Alerts
SMS Alerts *
Labels Pro+ Enterprise
trackingThis Supplied * *
Use Existing / Customer Supplied * *