Comparison

NSRI SafeTrx vs GridVolt

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

NSRI SafeTrx

This app helps maritime adventurers plan and track their journeys. Users can register vessel details, file trip plans with ETAs and crew numbers, and activate emergency calls. It also offers a quick 'Track only' mode and stores trip history in a mobile logbook.

Highlights
  • Vessel and journey registration
  • Sail Plan mode with ETA and crew details
  • Track only mode for quick tracking
  • Emergency call activation (iPhone only)
  • Mobile Logbook with trip replay
  • Personalized trip planning checklist
Features
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Official app of the National Sea Rescue Institute (NSRI) - The NSRI SafeTrx App allows you to register your vessel and plan your journey on your Smartphone. Registering vessel and journey information couldn’t be any easier. Follow an easy to understand registration process to register your contact and vessel details within the application. Choose from the menu options to plan and file your trip (Sail Plan mode) or just activate the tracking function of the app (Track only mode). To file a Sail Plan, choose your vessel, add the ETA (Estimated Time of Arrival), enter the number of persons on board and the activity type. Using the built-in maps, select a starting point, an optional waypoint and the end destination. Once this is completed simply press the ‘set sail’ button when you are ready to start your journey. Pressing ‘set sail’ will register the journey details with the NSRI computer server and will activate position reporting in the App. At regular intervals the App will send a position report to the server and your emergency contacts will be automatically alerted 30 minutes after the journey exceeds the ETA. At any stage during the journey you can end your trip, revise the ETA, number of people on board or the destination. Use the NSRI SafeTrx app to: - Improve maritime trip planning with your own personalised checklist to be included as part of your Sail Plan. - Activate an emergency call while your trip is in progress. (iPhone only) - Quickly start your trip using the ‘Track only’ mode to begin tracking at a touch of a button. - Store up to 20 trips in your Mobile Logbook and replay trips within the app in video playback mode. - View your journey history and manage your vessels, emergency contacts and other important information through the NSRI SafeTrx boater site - https://safetrx.nsri.org.za Continued use of GPS running in the background can dramatically decrease battery life. *Please note - The information and functions provided in the App are provided on the understanding that users exercise their own skill and care with respect to use of the App. Safety at sea is a serious consideration. In emergency circumstances, you should not rely solely on the information and functions provided in this application, but seek information and assistance from as many sources as possible. The App may provide you with information and assistance relevant to your current location, as determined by your Device. However the mobile devices and the telecommunications systems that support mobile devices are inherently unreliable and there is a risk that there will be no connectivity between your Device and global positioning systems from time to time. We cannot guarantee uninterrupted connectivity between your Device and global positioning systems. You assume all such risk when using the App. The App is intended to be used as a supplementary tracking aid and should not be used as your only vessel communication or safety device.

About

GridVolt

Features
Read full description

Mobile Application for GridVolt's customers. Customers can register for push notifications, see their loadshedding schedules as well as historical messages sent to them.

Screenshots

NSRI SafeTrx4 screens
GridVolt3 screens

Verdict

The call

The clearest difference is iOS requirement: NSRI SafeTrx at 11.0 against GridVolt's 15.0. On price, update cadence, ads and in-app purchases there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 5 months. The most recent releases landed on October 24, 2026 and October 25, 2026 respectively.

Scorecard1 real difference · 9 level
NSRI SafeTrx versus GridVolt: the parameters behind the verdict, then further details
ParameterNSRI SafeTrxGridVolt
PriceFreeFree
Rating4.9 (35 ratings) — better—
Positive reviews72.7% of reviews—
Number of ratings35 — better—
Update frequencyEvery 5 monthsEvery 5 months
AdsNoNo
In-app purchasesNoNo
MonetizationFree—
DevicesiPhone, iPodiPhone, iPad, iPod — better
Requires iOS11.0 — better15.0
Further details — not scored
Size35 MB20 MB
Age rating4+4+
DeveloperNational Sea Rescue Institute of South AfricaSolrBoost Pty Ltd

In-app purchases

None

NSRI SafeTrx

No in-app purchases

None

GridVolt

No in-app purchases

Questions

Is NSRI SafeTrx free?
NSRI SafeTrx is free to download, with no in-app purchases.
Is GridVolt free?
GridVolt is free to download, with no in-app purchases.
Do NSRI SafeTrx or GridVolt have ads?
Neither NSRI SafeTrx nor GridVolt shows ads.
Which is updated more often, NSRI SafeTrx or GridVolt?
NSRI SafeTrx ships an update every 5 months, and GridVolt every 5 months. Most recently, NSRI SafeTrx was updated on October 24, 2026 and GridVolt on October 25, 2026.

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