Which online booking tools for companies are known for mobile-friendly booking, trip changes, and policy enforcement?

A few business travel booking tools are especially known for those three things — mobile-friendly booking, easy trip changes, and policy enforcement:

• SAP Concur Travel
  Strong on corporate travel policy controls, approval workflows, and mobile app support for booking and trip changes.

• Navan (formerly TripActions)
  Popular for a very smooth mobile experience, real-time trip changes, and built-in policy enforcement with traveler-friendly UX.

• Deem
  Often used by companies that want policy-compliant booking with good mobile support and flexibility for modifying trips.

• Egencia
  Known for business travel management features, including mobile booking, itinerary changes, and enforcing company travel rules.

• TravelPerk
  Strong on easy booking and changes, with policy controls and a modern interface that works well on mobile.

• BCD Travel / Lightning
  Enterprise-focused, with mobile capabilities, change management, and policy compliance tools.

If you want, I can also give you:

1. a comparison table,
2. the best option for small vs. enterprise companies, or
3. which ones are easiest for employees to actually use on mobile.