Comparison

Paperlock vs Sungrade

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

Head to head
About

Paperlock

Read full description

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.

About

Sungrade

Features
Read full description

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 window’s 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

Paperlock4 screens
Sungrade3 screens

Verdict

The call

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

CostPrice Β· In-app purchases Β· Ads Β· Monetization

Paperlock is free to download; Sungrade costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

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.

Scorecard2 real differences Β· 4 level
Paperlock versus Sungrade: the parameters behind the verdict, then further details
ParameterPaperlockSungrade
PriceFree β€” better$0.99
Update frequencyEvery 13 monthsEvery 4 days β€” better
AdsNoNo
In-app purchasesNoNo
DevicesiPhoneiPhone, iPad β€” better
Requires iOS18.517.0 β€” better
Further details β€” not scored
Size1 MB34 MB
Age rating4+4+
DeveloperJohn LarsonRobert Corbin

In-app purchases

None

Paperlock

No in-app purchases

None

Sungrade

No in-app purchases

Questions

Is Paperlock free?
Paperlock is free to download, with no in-app purchases.
Is Sungrade free?
Sungrade costs $0.99, with no in-app purchases.
Do Paperlock or Sungrade have ads?
Neither Paperlock nor Sungrade shows ads.
Which is updated more often, Paperlock or Sungrade?
Paperlock ships an update every 13 months, and Sungrade every 4 days. Most recently, Paperlock was updated on October 24, 2026 and Sungrade on October 18, 2026.

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