Comparison

Pendulum vs DJOLT

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

Head to head
About

Pendulum

This app helps you manage your pen pal relationships by tracking correspondence. Record when you send and receive letters, note writing materials, and set reminders to stay in touch. Sync your data across devices for seamless management.

Highlights
  • Track sent and received letters
  • Record pen, ink, and paper used
  • Set reminders to write and post
  • Monitor letter delivery times
  • iCloud sync across devices
Read full description

Pendulum - keep track of your pen pals! • Add your friends, record when you send them letters or they send something to you. See how long it takes for your letters to arrive! • Record what pen, ink, and paper you used to write to each person, to keep the variety going each time you write. • Reminders to write back, or to post letters you've written but have sat by the front door for ages; you won't forget to stay in touch again. • Sync via iCloud, so you can keep up to date regardless of what device you have to hand.

About

DJOLT

Features
Read full description

DJOLT is built for the maritime, cruise, and yachting industries but adapts seamlessly to a variety of onshore settings. Designed to deliver high-priority alerts directly to your device within a local network, DJOLT eliminates the need for uninterrupted internet access, ensuring reliability in environments where connectivity may be limited. DJOLT operates with a locally installed DJOLT Server, using Local Push Connectivity, to ensure alert delivery even if the app is closed or running in the background. Supported Features: - View active and historical alerts, with timestamps for received and acknowledged alerts. - Acknowledge alerts within the app or by long-pressing a banner notification. - On/Off Duty setting to manage availability. - Critical Alerts that bypass Silent Mode, preventing missed notifications for high-priority situations. - Acknowledge and silence an alert for all recipients when acknowledged by a single user. - Adjustable alert volume. - Test notifications for setup verification. While optimized for maritime use, DJOLT’s on-premises functionality makes it equally effective for industrial facilities, manufacturing plants, and security systems, supporting reliable oversight and timely response to critical situations.

Screenshots

Pendulum4 screens
DJOLT3 screens

Verdict

The call

The clearest difference is in-app purchases: DJOLT at none against Pendulum's 5. On price, update cadence, ads and device support 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. Pendulum sells 5 one-off in-app purchases. DJOLT asks for nothing beyond the download.

UpkeepUpdate frequency

Pendulum ships an update every 9 days, DJOLT fortnightly. The most recent releases landed on September 10, 2026 and September 9, 2026 respectively.

Scorecard1 real difference · 9 level
Pendulum versus DJOLT: the parameters behind the verdict, then further details
ParameterPendulumDJOLT
PriceFreeFree
Rating4.2 (16 ratings) — better—
Positive reviews66.7% of reviews—
Number of ratings16 — better—
Update frequencyEvery 9 days — betterFortnightly
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchases—
DevicesiPhone, iPadiPhone, iPad
Requires iOS17.0 — better17.5
Further details — not scored
Size5 MB69 MB
Age rating4+4+
DeveloperBenjamin CardyMatthew Johl

In-app purchases

5 purchases

Pendulum

One-time5
  • Extra Fine Tip$0.99
  • Fine Tip$1.99
  • Medium Tip$3.99
Show 2 more
  • Broad Tip$5.99
  • Stub Tip$9.99
None

DJOLT

No in-app purchases

Questions

Is Pendulum free?
Pendulum is free to download, with in-app purchases available.
Is DJOLT free?
DJOLT is free to download, with no in-app purchases.
Do Pendulum or DJOLT have ads?
Neither Pendulum nor DJOLT shows ads.
Which is updated more often, Pendulum or DJOLT?
Pendulum ships an update every 9 days, and DJOLT fortnightly. Most recently, Pendulum was updated on September 10, 2026 and DJOLT on September 9, 2026.

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