# RailPros OTSS > On-track safety tool for managing flags, derails, and switch locks with GPS verification. (iPhone/iPad app by RailPros.) - Source: https://appshunter.io/ios/app/railpros-otss/id6466648988 (this page in markdown: same URL + `.md`) - Developer: [RailPros](https://appshunter.io/developer/1499013686) - Category: Utilities - Price: Free - Rating: 3.67/5 from 3 App Store ratings - Age rating: 4+ - Requires: iOS 13.4 · 42 MB - Languages: English - Released: 2023-10-23 - Data updated: 2026-07-08 - Monetization: free - User reviews in markdown: https://appshunter.io/ios/app/railpros-otss/id6466648988/reviews.md ## What is RailPros OTSS? The On-Track-Supplemental-Safety (OTSS) app was created as a supplementary tool for field personnel to prevent leaving conditional stop order flags displayed beyond their intended time. The initial design included a simple interface to set physical locations of flags using gps coordinates. The flag locations are set previous to a jobs start date and, also, serves as an additional safe guard to ensure the flagging employees are able to access their flag locations. Upon the start of a flaggers conditional stop order, when flags are being initially placed, the flagger "opens" their flags in the app . The apps logic utilizes the flaggers current GPS location, in relation to the flags preset GPS location in the system, to ensure they are within a predetermined distance from the flag location they intend to "open". If they are not, the system will not allow the flag in question to be "opened". Conversely, when conditional stop order expires, the flagger needs to be within the same predetermined distance to "close" each flag associated with the conditional stop order. Since the inception of the OTSS system, several class one railroads have provided RailPros with the GPS coordinates of their mileposts down the hundreth of a mile, and those coordinates have been integrated into the OTSS system to automatically populate the location of a flaggers chosen track flag locations. After the successful roll-out of the OTSS app, portable derails, switch locks, and their associated flag locations were added to the system. Working much the same way as the conditional stop order flags, derail locations, switch locations, and their associated flag locations are pre-set by the flagger prior to the use of any type of the aforementioned on-track-safety tools, and must be opened and closed as they are utilized. OTSS has been developed to send corresponding alerts and notifications to both the flagger and his/her management team concerning flags not yet "opened", protections expiring soon, protections that are expired but still have corresponding flags not yet "closed", and we have most recently added the ability for a flagger to report for duty before his/her shift starts, and go off duty when he/she has finished work on the railroads property. Additionally, during the pandemic, a paperless job briefing was created within the app to maintain social distancing on job sites protecting workers on railroad property. The job briefing system is still in use today. RailPros is continuing to develop and fine tune the OTSS sytem to this day. The OTSS app has reduced incidents involving our track protection tools by over 50% year over year. ## Key features - GPS-based flag location verification - Open/close flags, derails, and switch locks - Automated alerts for flag status - Paperless job briefing system - Reporting for duty and off duty - Reduced safety incidents by over 50% ## Frequently asked questions about RailPros OTSS ### What is RailPros OTSS used for? RailPros OTSS is used by railroad field personnel to manage on-track safety equipment like flags, derails, and switch locks. It ensures these are properly opened and closed at designated GPS locations to enhance safety. ### How does RailPros OTSS use GPS? The app uses GPS coordinates to verify that personnel are within a predetermined distance of the physical location of flags, derails, or switch locks before they can be opened or closed. This prevents equipment from being left in an unsafe state. ### What kind of alerts does RailPros OTSS send? RailPros OTSS sends alerts to both the flagger and their management team. These notifications cover flags not yet opened, protections nearing expiration, and protections that have expired but still have associated flags not closed. ### Does RailPros OTSS have a job briefing feature? Yes, RailPros OTSS includes a paperless job briefing system. This feature was developed to help maintain social distancing on job sites and is still in use today. ### How often is RailPros OTSS updated? The latest version of RailPros OTSS is 1.7, and it was last updated on April 22, 2025. The developer, RailPros, continues to develop and fine-tune the system. ### What is the age rating for RailPros OTSS? RailPros OTSS has an age rating of 4+. This indicates it is suitable for a wide range of users, including younger individuals, though its primary audience is adult railroad personnel. ### How has RailPros OTSS impacted safety incidents? Since its inception, the OTSS app has significantly reduced incidents involving track protection tools. RailPros reports a reduction of over 50% year over year in such incidents. ### Is RailPros OTSS available on multiple platforms? The provided data does not specify platform compatibility beyond its general availability as a mobile application. Users should check their respective app stores for device compatibility. ## Version history (last 1 release) ### 1.7 — 2025-04-22 You can now sign out at the end of your shift by following the link in messages. ## More apps by RailPros - [eCFR: FRA](https://appshunter.io/ios/app/ecfr-fra/id1499013687) All apps by RailPros: https://appshunter.io/developer/1499013686 --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-07-08.*