Prometheus Mobile STO vs Arrk
Price, ratings, monetisation and update history for both apps, side by side ā with what reviewers say about each.
Prometheus Mobile STO
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Prometheus STO Mobile is a Prometheus Group Platform that is an easy-to-use interface and framework to address shut-down, turn-around, and outages of heavy assets in various industries. Prometheus Group is the leading enterprise asset management software solution provider, covering your plant maintenance, operations, and safety needs from planning to execution and beyond.
Arrk
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Arrk is a native iPhone app for your Radarr and Sonarr servers. Browse your library, add missing titles, choose releases and track downloads without opening a browser. ⢠Connect directly to your servers over local Wi-Fi or a VPN such as Tailscale. No Arrk account and no cloud relay. ⢠Server addresses and API keys stay securely in your iPhone keychain. ⢠Automatic discovery finds Radarr and Sonarr on your network, so you do not need to look up IP addresses or ports. ⢠See upcoming movies and episodes from every server in one calendar, grouped by date, with premieres and finales highlighted. ⢠Browse each library as a fast poster grid or compact list, with search, sorting and filters for available, missing and monitored titles. ⢠See artwork, cast, ratings, seasons and files together on clear, detailed pages. ⢠Add titles using your existing quality profiles and root folders, or search releases manually and compare quality, size and seeders. ⢠View both queues on one screen, follow progress in real time and get notified when a download finishes. Server health and free disk space are always close at hand. ⢠Search your history of grabs, imports and failures, with the tools you need to deal with anything that gets stuck. ⢠Make it yours with an accent colour, light or dark mode, haptics and animations. Available in English, Italian, Spanish, German and French. Arrk requires a Radarr and/or Sonarr installation that your iPhone can reach over local Wi-Fi or VPN.
Screenshots
Verdict
The clearest difference is update cadence: Arrk at every 3 days against Prometheus Mobile STO's every 2 months. Prometheus Mobile STO's advantage is device support (3 vs 1) and iOS requirement (13.0 vs 16.4). On price, ads and in-app purchases there is nothing between them.
Scored on Price Ā· Rating Ā· Positive reviews Ā· Number of ratings Ā· Update frequency Ā· Ads Ā· In-app purchases Ā· Monetization Ā· Best chart rank Ā· Devices Ā· Requires iOS
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
Prometheus Mobile STO ships an update every 2 months, Arrk every 3 days. The most recent releases landed on October 19, 2026 and October 16, 2026 respectively.
| Parameter | Prometheus Mobile STO | Arrk |
|---|---|---|
| Price | Free | Free |
| Update frequency | Every 2 months | Every 3 days ā better |
| Ads | No | No |
| In-app purchases | No | No |
| Devices | iPhone, iPad, iPod ā better | iPhone |
| Requires iOS | 13.0 ā better | 16.4 |
| Further details ā not scored | ||
| Size | 34 MB | 49 MB |
| Age rating | 17+ | 4+ |
| Developer | Prometheus Group, Inc | Alessandro Mazzon |
In-app purchases
Prometheus Mobile STO
No in-app purchases
Arrk
No in-app purchases
Questions
Is Prometheus Mobile STO free?
Is Arrk free?
Do Prometheus Mobile STO or Arrk have ads?
Which is updated more often, Prometheus Mobile STO or Arrk?
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