Comparison

Sisyphus Tasks vs Tethra.ai

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

Head to head
About

Sisyphus Tasks

This app helps you manage your tasks and events in one place, offering quick ways to add, edit, and organize your schedule. It provides customizable alerts and powerful search to ensure you never forget important items.

Highlights
  • Drag and drop event management
  • Quick event creation
  • Duplicate events for schedules
  • Contextual actions for common tasks
  • Automatic task sorting
  • Customizable alerts
  • Powerful search functionality
Read full description

Never forget anything again! Sisyphus keeps all your tasks and events in one place and gives you full control over your day. All you need to do is write it down and Sisyphus remembers it for you. Manage your agenda faster and without friction. Not only can you add new items quickly, but you can also edit them in seconds: • Move items by simply dragging them to a date or list. • Tap and hold any day in the timeline or month view to create a new entry. • Enter your shift or class schedule in record time by duplicating events. Common actions are no longer a chore. Join a meeting with a tap or quickly skip a recurring to-do with additional useful context actions available everywhere. TASK MANAGER: All of your tasks are automatically sorted for you. Planning your open tasks is easy when you can see them at a glance. ORGANIZER: Choose colors and icons for your work or school calendars and grocery or project lists. Drag and drop them into any order you like. CONTACTS: Birthdays and anniversaries are shown right in your agenda and new contacts can be easily added. ALARM CLOCK: Get reminded before or after an event, at a date or at a location with highly customizable alerts. From your contacts' birthdays to your daily medication, Sisyphus can notify you about anything you want to remember. JOURNAL: The powerful search lets you find the date of any past event or when you completed a task, no matter how long ago it was.

About

Tethra.ai

Features
Read full description

Your personal AI team that actually gets work done. Tethra gives you a team of AI agents you can hire, chat with, and delegate real tasks to — all from your phone. If you're juggling too many projects, drowning in to-dos, or just need help staying on top of everything, your AI crew is ready. Some features and content require in-app purchases or a subscription. HIRE AI AGENTS FOR ANY ROLE Browse a catalog of specialized agents — project managers, operations specialists, researchers, writers, analysts, and more. Each agent has unique skills, a distinct personality, and memory that persists across every conversation. Hire the roles you need. Fire the ones you don't. Build a team that fits how you work. CHAT IN REAL TIME Message your agents like you'd text a coworker. Ask questions, give instructions, brainstorm ideas — they respond instantly in threaded group conversations. @mention specific agents or let the intelligent router figure out who should handle each message. Your team is always available, always responsive. MANAGE TASKS VISUALLY Organize work on kanban boards with drag-and-drop simplicity. Create tasks, set priorities, and move them across columns as work progresses — from Backlog to Done. Assign tasks to your AI agents and they pick them up autonomously. No follow-ups needed. AGENTS THAT LEARN AND REMEMBER Unlike basic chatbots, Tethra agents have a four-layer memory system: - Company Memory — shared knowledge your whole team can access - Agent Memory — individual patterns and decisions each agent learns - Conversation Memory — context that carries across chats automatically - Your Preferences — personal working style and overrides The more you use them, the better they get. STAY ON TOP OF EVERYTHING Your dashboard shows active agents, open tasks, and live conversations at a glance. Push notifications with deep linking keep you connected — tap any alert to jump straight to the action. DESIGNED FOR FOCUS A refined dark interface with fluid animations makes long sessions effortless. Every interaction is fast, intuitive, and built to keep you in flow. FLEXIBLE PRICING Purchase credits as you go or subscribe to Pro for premium features and the best value. Credit Packs (one-time purchase, credits never expire): - 1,000 Credits - 50,000 Credits - 100,000 Credits - 250,000 Credits Pro Subscriptions: - Pro Weekly - Pro Monthly - Pro Annual (best value) Pro subscriptions provide access to premium agent capabilities, priority response times, and a monthly credit allowance. Payment will be charged to your Apple ID account at confirmation of purchase. Subscriptions automatically renew unless canceled at least 24 hours before the end of the current period. Your account will be charged for renewal within 24 hours prior to the end of the current period at the rate of your selected plan. You can manage and cancel your subscriptions by going to your Account Settings in the App Store after purchase. Any unused portion of a free trial period, if offered, will be forfeited when you purchase a subscription. Terms of Use: https://tethra.ai/terms Privacy Policy: https://tethra.ai/privacy

Screenshots

Sisyphus Tasks4 screens
Tethra.ai4 screens

Verdict

The call

The clearest difference is in-app purchases: Sisyphus Tasks at none against Tethra.ai's 7. Tethra.ai's advantage is update cadence (every 2 weeks vs every 2 months) and device support (3 vs 1). On price and ads 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. Tethra.ai sells 7 in-app purchases, starting at $4.99 per 7 days. Sisyphus Tasks asks for nothing beyond the download.

UpkeepUpdate frequency

Sisyphus Tasks ships an update every 2 months, Tethra.ai every 2 weeks. The most recent releases landed on October 12, 2026 and October 14, 2026 respectively.

Scorecard4 real differences · 6 level
Sisyphus Tasks versus Tethra.ai: the parameters behind the verdict, then further details
ParameterSisyphus TasksTethra.ai
PriceFreeFree
Rating5.0 (6 ratings) — better—
Positive reviews75.0% of reviews—
Number of ratings6 — better—
Update frequencyEvery 2 monthsEvery 2 weeks — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree—
DevicesiPhoneiPhone, iPad, iPod — better
Requires iOS18.015.5 — better
Further details — not scored
Size30 MB48 MB
Age rating4+17+
DeveloperGregor HermanowskiGitspark Technologies, LLC

In-app purchases

None

Sisyphus Tasks

No in-app purchases

7 purchases

Tethra.ai

Subscriptions3
  • Pro Weekly$4.997 Days
  • Tethra$14.991 Month
  • Tethra$99.991 Year
One-time4
  • 10,000 Credits$0.99
  • 50,000 Credits$4.99
  • 100,000 Credits$9.99
Show 1 more
  • 250,000 Credits$24.99

Questions

Is Sisyphus Tasks free?
Sisyphus Tasks is free to download, with no in-app purchases.
Is Tethra.ai free?
Tethra.ai is free to download, with in-app purchases available.
Do Sisyphus Tasks or Tethra.ai have ads?
Neither Sisyphus Tasks nor Tethra.ai shows ads.
Which is updated more often, Sisyphus Tasks or Tethra.ai?
Sisyphus Tasks ships an update every 2 months, and Tethra.ai every 2 weeks. Most recently, Sisyphus Tasks was updated on October 12, 2026 and Tethra.ai on October 14, 2026.

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