Motorcycle Performance App Development

Description:
I need a native iOS app (Swift/SwiftUI) that gives a rider turn-by-turn navigation and records riding data from a handset mounted on a motorcycle, within geofenced zones. This is for a research pilot, not a public release. It is iOS only, with no Android and no App Store launch (TestFlight is fine).
Navigation
• Route planning to a chosen destination, with turn-by-turn guidance, a clear map display and spoken or visual prompts suitable for a mounted phone
• Rerouting if the rider leaves the route
• Please state which navigation approach you'd use (for example Apple MapKit, or a third-party SDK such as Mapbox) and any licence or usage costs I would carry
• Recording must run independently of navigation, so a navigation crash or reroute never interrupts data capture
Zones
• The zones are derived from public data. I will prepare the zone file myself (coordinates and radius per zone, in a simple format such as GeoJSON or CSV), and the app only needs to load it.
• The zone set could run to dozens or hundreds of locations, so the app needs a sensible way of working within iOS's limit on simultaneously monitored regions, for example by monitoring only the nearest zones and refreshing them as the rider moves.
Recording
• Load the zone file
• Log every zone entry and exit with a timestamp, tied to the ride
• Record GPS location, route, speed and distance in the background, with the screen off
• Record motion-sensor data (accelerometer and gyro), timestamped and synchronised with GPS
• Store each ride locally and export the raw data, including the zone events, so I can analyse it on a Windows PC
Please note
• A phone can't read real braking or throttle input from the bike. Acceleration and braking will be estimated from GPS and motion sensors, and the app should label them as estimates and flag low-confidence readings rather than present them as facts.
• iOS geofence entry/exit detection can be delayed or imprecise. Please explain how you'd handle this, including GPS drift near zone boundaries at riding speed.
• Please allow for vibration, phone orientation and battery use on a long run, especially with navigation and recording running together.
• Testing will be on a real iPhone 15 Plus (iOS 27.0.1).
Communication
• Fluent, professional English, written and spoken, is essential. You will need to discuss technical detail clearly and write clear documentation and code comments.
• Please write your proposal yourself, in your own words. Proposals that look copied or generic will be ignored.
Payment and acceptance
• Payment is by a single escrow milestone for the full agreed price. I will fund it when we agree terms, so the money is secured, and I will release it once I have tested the working app on my own motorcycle and iPhone.
• Acceptance means the app installs from TestFlight, navigates a real route, records continuously with the screen off for the full ride, logs zone entries and exits, and exports the data intact. Any faults found in testing must be fixed before release.
• Please price on this basis and tell me if you have any concerns about it.
How we'll work
• A full written specification will be shared once a Milestones Global NDA is signed.
• Code goes into a private Git repository that I own.
To bid, please include
1. Examples of native iOS work using navigation, background location, geofencing or CoreMotion (or tell me honestly if you have none)
2. Confirmation that you will build in Swift/SwiftUI, not a cross-platform framework
3. Your proposed navigation approach and any ongoing costs
4. How you'd handle a large zone set within iOS's region-monitoring limit, and boundary drift
5. Your total price and timeline
Budget: Based on quotes