The verdict in three sentences
A custom field mobile app costs between 30,000 and 70,000 EUR excl. tax in 2026 depending on offline mode, client signature and ERP sync. The most profitable feature is offline mode: without it, your technicians waste time re-entering reports back at the office. Each equipped technician saves 5 to 10 hours/week, paying back the app in under a year from 8 technicians upward.
How much a field app costs in 2026
Price depends on business features: a simple digital intervention logbook is not the same as an ERP-connected app with proof of visit.
| App scope | 2026 price (EUR excl. tax) | Timeline |
|---|---|---|
| Intervention reports + photos | 30,000 - 40,000 | 3 months |
| + Offline mode + client signature | 40,000 - 55,000 | 4 months |
| + ERP sync + scheduling | 55,000 - 70,000 | 5 months |
| Geolocation + proof of visit | + 8,000 - 15,000 | + 1 month |
| Annual maintenance | 15 - 20% of project | recurring |
Offline mode is about 20 to 30% of the budget but it's what delivers on-site time savings where 4G coverage is unstable.
PWA vs native app
Two technical approaches, two cost and usage profiles.
| Criterion | PWA (web app) | Native app |
|---|---|---|
| Development cost | 25,000 - 45,000 EUR | 40,000 - 70,000 EUR |
| Offline mode | Good (cache) | Excellent (local database) |
| Camera/GPS access | Adequate | Full and smooth |
| Touch signature | Yes | Yes, smoother |
| Installation | Link, no store | Via App Store/Play Store |
| Update time | Instant | Store review 1-3 days |
| Maintenance/year | 4,000 - 8,000 EUR | 8,000 - 14,000 EUR |
For technicians often in poorly covered areas with intensive camera and GPS use, native is more robust. For a tight budget and lighter use, a PWA is enough.
Mini case study
Sarah, COO of an HVAC maintenance firm in Lyon, manages 12 technicians. Each loses about 7 hours/week to report re-entry and trips back to the office. At a loaded cost of 35 EUR/hour, that's 245 EUR/technician/week, i.e. 12 x 245 x 45 weeks = 132,300 EUR/year of wasted time.
She invests 52,000 EUR excl. tax in a native app with offline mode and ERP sync, plus 10,000 EUR annual maintenance. The app removes 6 of the 7 lost hours per technician: a gain of 113,000 EUR/year. The app pays for itself in about 6 months, maintenance included.
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FAQ
Do I really need offline mode?
Yes for any technician working in basements, rural areas or parking lots. Without it, the app becomes unusable the moment connectivity drops and technicians revert to paper.
PWA or native for my technicians?
If camera, GPS and offline use is intensive, choose native (40,000 - 70,000 EUR). For lighter use and a constrained budget, a PWA (25,000 - 45,000 EUR) does the job.
Is the client signature legally valid?
A timestamped, geolocated touch signature is solid proof of visit, admissible in the event of a dispute over an intervention.
How much time does a technician save?
On average 5 to 10 hours/week by removing re-entry and office trips. Across a 12-person team this often exceeds 100,000 EUR/year.
Can the app connect to our ERP?
Yes, via API. Budget 55,000 to 70,000 EUR for an app with two-way ERP sync (interventions, inventory, billing).
Let's scope your project. Tell us the number of technicians, your ERP and whether offline mode is essential for an indicative PWA or native budget. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.
Mohamed Bah
Fondateur, Kolonell
Passionate about digital and entrepreneurship in Africa, Mohamed has been helping Sénégalese businesses with their digital transformation since 2020. Founder of Kolonell, he believes every SME deserves a professional and accessible online présence.
