Offline-first mobile architecture vs cloud SaaS for field apps

Hi everyone,

I have been researching and building a mobile utility for field contractors and service workers. During the development process, one major architectural decision came up: Cloud vs 100% Offline.

Many field professionals (contractors, technicians, inspectors) work in areas with poor or zero cellular coverage. Cloud-based SaaS tools often freeze or fail to sync in these conditions.

On the other hand, an offline-first approach keeps all data, documents, and photos strictly local on the device, ensuring instant speed and complete privacy.

I'm curious to hear thoughts from other developers and product builders:

Do you think offline-first mobile apps have a competitive advantage in field service niches, or is cloud sync an absolute requirement for modern users?