Comparison

Shepherd Shield vs Vox Petri

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

Head to head
About

Shepherd Shield

This app provides real-time threat assessments based on location, using a color-coded alert system. Users can customize alerts for various threats and receive notifications for pre-set safety spots. It includes emergency contact buttons for 911 and a dispatch center.

Highlights
  • Real-time threat assessment
  • Color-coded alert index
  • Customizable alert categories
  • Map-based data view
  • Pre-set safety spot notifications
  • SOS and Call 911 buttons
Features
Read full description

When seconds count, count on Shepherd Shield. Shepherd Shield is a mobile app for use on iPhone. When a subscriber is in an area, familiar or not, the Shepherd Shield alert system provides a real-time threat assessment based on a color-coded alert index: green, yellow, orange and red, the highest. Shepherd Shield alerts are issued when a subscriber comes in close proximity of a threat area, as determined by information obtained from law enforcement, emergency services, news reports and predetermined threat areas. The app’s debut in 2017 is in Washington State. Eventually, expansion is planned to the other 49 states, throughout North America and in other countries. Shepherd Shield users have a customized choice of categories, including high crime areas, active shooter alerts, terrorist threats, weather emergencies, and the addresses of registered sex offenders. Data can be viewed individually, as lists, and by using a map feature. Enable/disable the functions as you choose. There is also a “report” function so a subscriber may contribute information. In the worst-case emergency, such as an active shooter alert, the app would issue an alert warning. A user can pre-set their “Top 5 Safety Spots” such as a school, office building, etc., and should an alert happen at one of those spots, the user’s Shepherd Shield app would automatically send notice. The app includes a “Call 911” button and an “SOS” button which calls the 24/7 Shepherd Shield dispatch center (located in the USA). A user needs to have a cellular connection to make such a call. The app has been developed for Security Services Northwest, Inc., a multi-dimensional security company headquartered on Washington State’s Olympic Peninsula. “It’s about personal security,” says Joe D’Amico, SSNW President and owner since 1986, who started his career with a German Shepherd security patrol dog. As the father of five children, D’Amico started Shepherd Shield with the idea of protecting campus safety. “Shepherd Shield is your own German shepherd, your personal protector, in your pocket.” ============================Disclaimer============================ * The purpose of this application is to provide the user with alerts based on the security threats around them. This app is not intended be used as a primary security response application in the event of a threat. * This application makes use of the user location. This may, in turn, affect the battery performance of the user device. The user can turn off the Follow Me option if they want to turn off their location services.

About

Vox Petri

Features
Read full description

Vox Petri brings 145 years of papal encyclicals to your fingertips. Read the complete texts of 221 encyclicals from Leo XIII through Leo XIV, explore thematic connections across centuries of Church teaching, and visualize the web of citations linking documents together. Features include a full-text reader with paragraph-level bookmarks, 20 thematic threads tracing ideas like Human Dignity, Social Justice, and Faith & Reason across the tradition, and an interactive connection graph showing how encyclicals cite and build on each other. Future releases may include full text search and the ability to get answers to questions via large language model integrations to the encyclical corpus.

Screenshots

Shepherd Shield4 screens
Vox Petri4 screens

Verdict

The call

The clearest difference is in-app purchases: Vox Petri at none against Shepherd Shield's 2. Vox Petri also leads on update cadence (every 2 weeks vs every 2 months). On price, ads, device support and iOS requirement 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. Shepherd Shield sells 2 one-off in-app purchases. Vox Petri asks for nothing beyond the download.

UpkeepUpdate frequency

Shepherd Shield ships an update every 2 months, Vox Petri every 2 weeks. The most recent releases landed on November 2, 2026 and October 31, 2026 respectively.

Scorecard2 real differences · 8 level
Shepherd Shield versus Vox Petri: the parameters behind the verdict, then further details
ParameterShepherd ShieldVox Petri
PriceFreeFree
Rating3.3 (24 ratings) — better—
Positive reviews33.3% of reviews—
Number of ratings24 — better—
Update frequencyEvery 2 monthsEvery 2 weeks — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree—
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS16 — better16.4
Further details — not scored
Size108 MB85 MB
Age rating4+4+
DeveloperSecurity Services Northwest, Inc.Jonathan Liang

In-app purchases

2 purchases

Shepherd Shield

One-time2
  • One Month Subscription$5.00
  • One Year Subscription$29.95
None

Vox Petri

No in-app purchases

Questions

Is Shepherd Shield free?
Shepherd Shield is free to download, with in-app purchases available.
Is Vox Petri free?
Vox Petri is free to download, with no in-app purchases.
Do Shepherd Shield or Vox Petri have ads?
Neither Shepherd Shield nor Vox Petri shows ads.
Which is updated more often, Shepherd Shield or Vox Petri?
Shepherd Shield ships an update every 2 months, and Vox Petri every 2 weeks. Most recently, Shepherd Shield was updated on November 2, 2026 and Vox Petri on October 31, 2026.

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