Comparison

ToDo Calendar vs Deadline Backsolve

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

Head to head
About

ToDo Calendar

This app combines a calendar and task manager for streamlined daily planning. It offers a unified view of appointments and to-dos, with customizable features like holiday integration and dark mode. Stay organized with smart notifications and recurring event options.

Highlights
  • Integrated scheduling and to-dos
  • Holiday and custom date customization
  • Dark mode and font flexibility
  • Smart notifications and reminders
  • Recurring event setup
  • Device calendar sync
  • Quick glance widget
Features
Read full description

Simplify Your Life with dolfy – The Ultimate Calendar & Task Manager Experience the ease of managing your daily schedules and tasks with dolfy – the calendar app designed for stress-free organization. With dolfy's sleek interface, you can effortlessly merge your appointments and to-dos, providing a clutter-free overview of your month. It’s the ultimate calendar for those who crave simplicity and efficiency. ■ Essential Features for Streamlined Planning: ・Integrated Scheduling: Quickly add and view schedules and to-dos on one unified calendar. ・Holiday Customization: Personalize your calendar with national holidays and your own special dates. ・Week Start Customization: Start your week on Sunday or Monday to fit your planning style. ・Dark Mode: Reduce eye strain in low-light conditions with Dark Mode. ・At-a-Glance Organization: Prioritize and manage your time with a dual display that provides a comprehensive view of your calendar. ・Font Flexibility: Choose from various font sizes and styles for optimal visibility. ・Smart Notifications: Stay on top of your commitments with timely reminders and alerts. ・Recurring Events: Effortlessly set up repeat events for regular activities. ・Due Date Free To-Dos: Manage tasks without strict deadlines for flexible planning. ・Device Calendar Sync: Seamlessly sync your schedule across devices, including Google Calendar. ■ Key Functions to Boost Your Productivity: ・Easy Editing: Modify or delete entries with just a few taps. ・Customizable Dates and Times: Tailor your schedule entries to fit your life. ・Quick Glance Widget: Peek at your agenda without opening the app. ・Personalized Themes: Set a favorite photo as the app’s background for a unique touch. ・Quick Menu: Long press on an event in the list view to easily copy, move, or delete it dolfy is more than a calendar – it’s a companion to help you navigate the complexities of daily life. Download now and start organizing your time with confidence and style! ■ About Paid Plans Paid plans are automatically renewed each month. Renewal will take place within 24 hours before the end of the subscription period. If you do not cancel the auto-renewal at least 24 hours before the end of the subscription period, the subscription period will be automatically renewed. ■ Restoration when Changing Models When you change your handset, your previously purchased plan can be restored. Log in to your device with the same Apple ID you used to purchase the subscription, and tap "Restore Purchase" on the subscription screen. ■ Notes Cancellation of the current month's subscription will not be accepted. This plan is billed via Apple ID. ■ Privacy Policy https://calendartodo-b3833.web.app/privacy/ ■Terms of Use https://calendartodo-b3833.web.app/terms/

About

Deadline Backsolve

This app helps you adjust project plans when deadlines are at risk. It calculates the shortfall and suggests concrete adjustments like extending deadlines or reducing scope. The interface is currently in Japanese only.

Highlights
  • Calculates shortfall and suggests fixes
  • Adjusts plans based on available time
  • Learns user's real work pace
  • Offers recovery plan options
  • Focus timer that survives crashes
  • Offline functionality
  • JSON export/import for data transfer
Features
Read full description

When you realize you won't hit the deadline, what you actually need is the answer to "so what do I change?" Deadline Backsolve computes the shortfall and gives you concrete fixes: "push the deadline 3 days", "add 45 minutes per working day", "cut 4 pages". Real numbers, not a warning label. ■ Three inputs. Thirty seconds. What, how much, by when. That's the whole setup. Stages and per-weekday hours can wait until later. ■ Split the work into stages (new in 1.4) Thumbnails → pencils → inks → finishing, or outline → first draft → revision. Give each stage its share of the time per page, and the Today screen tells you exactly what to do: "Pencils 6 pages → then Inks 2 pages". The project screen shows each stage's progress. Stages are optional, and recovery plans keep working as before. ■ You only look at today The home screen says "Today: 8 pages." That's it. No Gantt charts, no dense tables. Tap "+1 page" when you're done. ■ It follows your real week One hour on weekdays, three on weekends? Your quota is distributed by the time you actually have. ■ It learns your real pace It starts from an estimate, then switches to your measured minutes per page once you have logged enough work. ■ Recovery plans, computed - Switch to a later registered deadline (with hours gained) - Extend the deadline by N days - Add N minutes per working day - Cut N units - Finish each unit within N minutes - Open up a day you had marked as rest Tap any of them to apply it to the plan immediately. ■ A focus timer that survives a crash It stores the start time, so closing the app never loses your session. It never plays a sound effect. ■ Your entries stay on your device No account. No ads. What you enter never leaves your device. To improve the app, only anonymous usage data (such as which screens are opened) is counted with Google Analytics (you can turn this off in Settings). Move it with a JSON export/import when you change phones. ■ One-time purchase. No add-ons. Everything is unlocked at purchase. Unlimited projects and logs. No subscription. ■ Available in English, Japanese, German, French, Korean and Traditional Chinese. Works for comics, novels, illustration books and merch, but also for articles, reports and theses — anything with an amount and a due date. Name the unit whatever you like.

Screenshots

ToDo Calendar4 screens
Deadline Backsolve4 screens

Verdict

The call

The clearest difference is price: ToDo Calendar at Free against Deadline Backsolve's $0.99. Deadline Backsolve's advantage is in-app purchases (none vs 1) and ads (none vs shown). On update cadence, 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

ToDo Calendar is free to download; Deadline Backsolve costs $0.99 up front. ToDo Calendar sells 1 in-app purchase, starting at $2.99 per month. Deadline Backsolve asks for nothing beyond the download.

UpkeepUpdate frequency

ToDo Calendar ships an update every 2 weeks, Deadline Backsolve weekly. The most recent releases landed on November 3, 2026 and October 31, 2026 respectively.

Scorecard5 real differences · 5 level
ToDo Calendar versus Deadline Backsolve: the parameters behind the verdict, then further details
ParameterToDo CalendarDeadline Backsolve
PriceFree — better$0.99
Rating4.5 (11 ratings) — better—
Positive reviews82.2% of reviews100.0% of reviews — better
Number of ratings11 — better—
Update frequencyEvery 2 weeksWeekly — better
AdsYesNo — better
In-app purchasesYesNo — better
MonetizationFree with in-app purchases — betterPaid
DevicesiPhone, iPadiPhone, iPad
Requires iOS18.017.0 — better
Further details — not scored
Size27 MB4 MB
Age rating4+4+
DeveloperTyabaAppDaisuke Yamaguchi

Customer experience

ToDo Calendar

All ratings11 ratings
Positive90.9%
Neutral0.0%
Negative9.1%
Written reviews45 reviews
Positive82.2%
Neutral6.7%
Negative11.1%

Deadline Backsolve

Written reviews2 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

1 purchases

ToDo Calendar

Subscriptions1
  • Monthly Subscription$2.991 Month
None

Deadline Backsolve

No in-app purchases

Questions

Is ToDo Calendar free?
ToDo Calendar is free to download, with in-app purchases available.
Is Deadline Backsolve free?
Deadline Backsolve costs $0.99, with no in-app purchases.
Do ToDo Calendar or Deadline Backsolve have ads?
ToDo Calendar shows ads; Deadline Backsolve does not.
Which is updated more often, ToDo Calendar or Deadline Backsolve?
ToDo Calendar ships an update every 2 weeks, and Deadline Backsolve weekly. Most recently, ToDo Calendar was updated on November 3, 2026 and Deadline Backsolve on October 31, 2026.

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