Comparison

FieldPrism vs Harding Charter Prep

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

Head to head
About

FieldPrism

This app standardizes field measurements by capturing photos with precise scaling and orientation. It uses on-device machine learning to correct perspective and rotation, creating measurement-ready images for scientific documentation. Multiple output formats and flexible naming options are available.

Highlights
  • On-device photogrammetric correction
  • Multiple output image formats
  • Known pixel-per-cm conversion factor
  • Printable FieldSheets included
  • Flexible naming workflows
  • Project-based organization
  • Optional GPS geotagging
Features
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App Store Description FieldPrism — Standardized Field Photography for Quantitative Science FieldPrism is designed to standardize the collection of field measurements using our photogrammetric templates. With each photo, you get standardized image orientation and precise scaling to enable simple downstream quantitative measurements — no tripods, no copy stands, and no manual calibration required. Place your specimen on one of our free printable FieldSheets, point your iPhone's camera, and let FieldPrism do the rest. On-device machine learning locates the photogrammetric markers in real time, corrects perspective and rotation, and produces a perfectly scaled image where every pixel corresponds to a known physical distance. The result is a reproducible, measurement-ready image dataset ideal for herbarium specimens, ecological samples, archaeological finds, forensic documentation, geological samples, classroom science, and any field workflow where scale matters. KEY FEATURES • On-device photogrammetric correction — a Core ML model detects ruler markers on your FieldSheet and automatically deskews, rotates, and scales every capture. • Three output images per capture — raw photo, a cropped "FP-Fit" image trimmed to the markers with adjustable padding, and an "FP-Expanded" image preserving the full scene. Each is paired with an overlay showing detected markers. • Known pixel-per-cm conversion factor — exported with every image so measurements in ImageJ, QGIS, Fiji, or any analysis tool are a one-step calculation. You can have FieldPrism output every image with a fixed 100 pixels = 1 cm. scaling. • Six printable FieldSheets included — A3, A4, A5, US Letter, Legal, and Tabloid. Share or AirPrint directly from the app. • Flexible naming workflows — choose QR-code scanning (up to 6 hierarchical levels), timestamp naming, manual entry, or build custom "Rolodex" naming schemes with reusable lists for catalog numbers, sites, plots, or taxa. Lots of ways to name and keep track of the images you take. • Project-based organization — group captures into projects, browse the project gallery, restore accidentally deleted projects, and keep long-running field campaigns tidy. • Optional GPS geotagging — attach precise coordinates to each image for scientific documentation. Toggle on and off at any time. • Customizable capture settings — select any back camera (ultrawide, wide, telephoto), set output resolution in pixels-per-cm, configure padding around markers, and set a "Herbarium Sheet" mode for mounted specimens. • Three live-view modes — see detection bounding boxes in real time, preview a live-deskewed image before you shoot, or frame with a classic viewfinder. PRIVACY FieldPrism does not collect, transmit, or store any of your data. There are no accounts, no analytics, no ads, and no trackers. All image processing happens on your device using Apple's Core ML. Photos, projects, and GPS coordinates stay on your iPhone unless you explicitly export or share them. WHO IT'S FOR • Botanists and herbarium digitization teams documenting pressed specimens • Ecologists and field biologists measuring leaves, fruits, fish, or scat • Archaeologists and forensic scientists recording in-situ finds • Geologists cataloging hand samples • Educators and students running reproducible classroom exercises • Anyone who has ever tried to measure something in a photo GETTING STARTED Print a FieldSheet from the Settings → FieldSheets tab (verify at 100% scale — black squares must be exactly 1 cm wide). Create a project and choose a naming method. Place your specimen on the sheet and capture. FieldPrism handles orientation, scaling, and filename. Export when you're ready. Questions, feedback, or feature requests? Tap the help icon in Settings — we'd love to hear how you're using FieldPrism in the field.

About

Harding Charter Prep

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Introducing the brand new app for Harding Charter Prep. NEVER MISS AN EVENT The event section shows a list of events throughout the district. Users can add an event to their calendar to share the event with friends and family with one tap. CUSTOMIZE NOTIFICATIONS Select your student's organization within the app and make sure you never miss a message. CAFETERIA MENUS Within the dining section, you'll find an easy to navigate, weekly menu, sorted by day and meal type. DISTRICT UPDATES In the Live Feed is where you'll find updates from the administration about what's going on in the district right now. Whether that's celebrating a student's success, or reminding you about an upcoming deadline. CONTACT STAFF & DEPARTMENTS Find relevant staff and department contacts under an easy-to-navigate directory.

Screenshots

FieldPrism4 screens
Harding Charter Prep4 screens

Verdict

The call

FieldPrism and Harding Charter Prep are too close to call on the numbers: across 5 compared parameters — price, ads, in-app purchases and device support among them — neither pulls far enough ahead to decide it. What separates them is feature set and interface, not measurable difference.

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.

ScorecardNo meaningful differences
FieldPrism versus Harding Charter Prep: the parameters behind the verdict, then further details
ParameterFieldPrismHarding Charter Prep
PriceFreeFree
Rating5.0 (2 ratings) — better—
Number of ratings2 — better—
Update frequency—Monthly
AdsNoNo
In-app purchasesNoNo
MonetizationFree—
DevicesiPhoneiPhone
Requires iOS17.016.0 — better
Further details — not scored
Size12 MB142 MB
Age rating4+4+
DeveloperWilliam WeaverHarding Charter Prep

In-app purchases

None

FieldPrism

No in-app purchases

None

Harding Charter Prep

No in-app purchases

Questions

Is FieldPrism free?
FieldPrism is free to download, with no in-app purchases.
Is Harding Charter Prep free?
Harding Charter Prep is free to download, with no in-app purchases.
Do FieldPrism or Harding Charter Prep have ads?
Neither FieldPrism nor Harding Charter Prep shows ads.

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