Paperlock vs Sungrade
Price, ratings, monetisation and update history for both apps, side by side β with what reviewers say about each.
Paperlock
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Paperlock is a locked drawer for the papers that matter. Your iPhone can already scan a page. Paperlock is where the scan goes afterwards, when it is something you would not leave lying around: a passport, a lease, a tax return, a medical record. LOCKED AND ENCRYPTED β’ Locks as soon as you leave it. Face ID, Touch ID or your passcode opens it again. β’ Every scan, PDF, name and note is encrypted with AES-256 before it is stored. β’ The key stays in your iPhone's Keychain, on this device only. YOUR PAPERS β’ Scan paper with the camera. Several pages become one PDF. β’ Import PDFs you already have. β’ Give each document a name and a note, and search through both. β’ Open a PDF, or share a copy when you choose. BACK UP ON YOUR TERMS β’ A backup is one encrypted file with its own password. β’ You decide where it goes. Paperlock does not upload it. β’ A vault password opens your documents on a new iPhone. PRIVATE BY DESIGN β’ No account, no cloud, no server, no analytics, no ads. β’ The app makes no network requests at all. GOOD TO KNOW β’ There is no password reset. Nobody else holds your key, so nobody can recover it for you. β’ There is no sync. Your documents are on one phone, and a backup file is how you move them. Paperlock was called Secure Document Vault. If you have it, this update keeps your documents and encrypts them the first time you open it.
Sungrade
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Compare saved windows for modeled direct sun during a specific date and daytime block instead of relying only on annual averages. HOW IT WORKS 1. Open Compare and tap Sun schedule. 2. Choose a date, start and end hour, and whether to rank for more or less direct sun. 3. Compare the saved windows and share the time-block report. Saved windows, annual and seasonal comparisons, manual coordinates and plant reference tools remain available. WHAT TO KNOW Times use each windowβs local clock and exclude the end hour. The five-minute vertical-window model uses saved facing direction and horizon obstructions. It does not measure indoor brightness, glare, heat, weather or plant growth. Glass and unsaved obstacles affect actual light. Zero modeled direct sun does not mean darkness. iPhone and iPad.
Screenshots
Verdict
The clearest difference is price: Paperlock at Free against Sungrade's $0.99. Sungrade's advantage is update cadence (every 4 days vs every 13 months). On ads, in-app purchases, device support and iOS requirement there is nothing between them.
Scored on Price Β· Rating Β· Positive reviews Β· Number of ratings Β· Update frequency Β· Ads Β· In-app purchases Β· Monetization Β· Best chart rank Β· Devices Β· Requires iOS
Paperlock is free to download; Sungrade costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.
Paperlock ships an update every 13 months, Sungrade every 4 days. The most recent releases landed on October 24, 2026 and October 18, 2026 respectively.
| Parameter | Paperlock | Sungrade |
|---|---|---|
| Price | Free β better | $0.99 |
| Update frequency | Every 13 months | Every 4 days β better |
| Ads | No | No |
| In-app purchases | No | No |
| Devices | iPhone | iPhone, iPad β better |
| Requires iOS | 18.5 | 17.0 β better |
| Further details β not scored | ||
| Size | 1 MB | 34 MB |
| Age rating | 4+ | 4+ |
| Developer | John Larson | Robert Corbin |
In-app purchases
Paperlock
No in-app purchases
Sungrade
No in-app purchases
Questions
Is Paperlock free?
Is Sungrade free?
Do Paperlock or Sungrade have ads?
Which is updated more often, Paperlock or Sungrade?
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