Comparison

OneCal vs VOIDTASK

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

Head to head
About

OneCal

Consolidate all your Google Calendar, Outlook, and iCloud events into a single, intuitive interface. Manage your schedule, create events, and share booking links effortlessly. Sync calendars in real-time for seamless team collaboration and to avoid double-bookings.

Highlights
  • Unified calendar view
  • Event creation and management
  • Scheduling and booking links
  • Real-time availability sync
  • Team calendar collaboration
  • Customizable reminders and attendees
Features
Read full description

ALL YOUR CALENDARS, IN ONE APP Stop juggling between Google Calendar, Outlook, and iCloud. OneCal brings all your calendars together in one clean and organized app, so you can focus on what matters instead of keeping track of where your events live. Over 10,000 customers trust OneCal for its reliability, simple design, and responsive support. UNIFIED CALENDAR VIEW See every event from every account in one place. Switch between Day, 3-Day, Week, and Month views. Turn individual calendars on or off, swipe between dates, and pull down to refresh. All-day events, overlapping meetings, and time zone labels are handled cleanly, so your schedule is always clear at a glance. AI ASSISTANT Ask OneCal about your schedule in plain language. Find out what is on today, when you are free tomorrow, or when a teammate has a gap. Ask it to create an event, block focus time, move a meeting, or set up a repeating event. It shows a summary before anything changes. It can also check your calendar syncs, manage your booking links, and answer questions about how OneCal works. Nothing is created, edited, or deleted without your approval. EVENT MANAGEMENT Create events by tapping the plus button, or hold and drag on a time slot to set a custom duration. Add locations, descriptions, reminders, attendees, and video links for Google Meet, Microsoft Teams, or Zoom. Mark events as busy or free. Set up repeating events that run daily, weekly, monthly, yearly, or on a custom pattern. Edit a single occurrence or the whole series. Reply to invitations with an optional note, and join video calls with one tap. REMINDERS AND ATTENDEES Set several reminders for each event, from minutes to days in advance. Add attendees by email and track their replies. See at a glance how many guests are coming, unsure, or have not answered yet. SCHEDULING AND BOOKING LINKS Share a scheduling link and let other people book time with you. No more emails back and forth to find a time that works. Create individual booking links for one-on-one meetings, or collective links so a group can be booked together. Set durations, add buffer time around meetings, require approval, and style your booking pages to match your brand. Manage all your bookings in the app, including upcoming, unconfirmed, past, and cancelled ones. Confirm, reject, or reschedule with a tap. AVAILABILITY SYNC Sync your calendars in real time to avoid double bookings. Set up one-way or two-way sync between any mix of Google Calendar, Outlook, and iCloud calendars. Choose exactly what gets copied, such as titles, descriptions, participants, locations, and meeting links. Keep sensitive details private by marking synced events as private or free. Exclude events by color, and pause or resume a sync whenever you need. TEAM COLLABORATION View your team members' calendars and availability side by side. See who is free, plan meetings across time zones, and keep everyone on the same page. Invite team members, manage their roles, and coordinate schedules. A great fit for distributed teams. PERSONALIZE YOUR EXPERIENCE Choose a light, dark, or system theme. Set your preferred hour format, first day of the week, default event duration, and time zone. Rename calendars, change their colors, or hide the ones you do not need. PRIVACY AND SECURITY Your data stays yours. OneCal connects through OAuth2, so we never store your passwords and never analyze your calendar data. All information is encrypted in transit and at rest on secure AWS infrastructure. We ask only for the minimum permissions required. The AI Assistant sees only what it needs to answer you, and your data is never used to train AI models. GET STARTED TODAY Connect your Google, Outlook, and iCloud calendars in seconds and take control of your schedule. Questions or feedback? Write to us at contact@onecal.io Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://www.onecal.io/privacy

About

VOIDTASK

This app offers a unique, dark-themed interface for managing tasks with advanced AI assistance. It visualizes task relationships, includes focus modes, OCR scanning, and voice input for efficient workflow. Designed for speed and privacy, it keeps all data on-device.

Highlights
  • AI-powered task creation and management
  • Dark terminal-grade interface
  • Visual knowledge graph of tasks
  • Distraction-free focus modes
  • OCR and voice task input
  • On-device AI assistant
  • Streak tracker for accountability
Features
Read full description

VOID//TASK is the Productivity Operating System built for people who work fast, and refuse to settle for software that looks like it was designed in 2015. Every screen is crafted with a dark terminal-grade interface — monospaced type, neon accents, scanline overlays, and zero visual clutter. This is what task management looks like when it is engineered, not decorated. — COMMAND YOUR QUEUE — Create, prioritize, and manage tasks with military-grade precision. Four priority tiers (CRIT / HIGH / MED / LOW), eight project namespaces, and time estimates from 15 minutes to 48 hours. Drag to reorder. Search instantly. Archive when done. Speak your mind and the AI in the NEXUS view will create your project and tasks. — AI DAEMON — An on-device AI assistant lives inside the app. Talk to it. Tell it what you need to remember. The Daemon extracts task titles, priorities, estimates, and project tags from natural conversation — then injects them directly into your queue. No cloud. No latency. Private by design, powered by Apple Intelligence. — NEXUS KNOWLEDGE GRAPH — See your tasks the way your brain connects them. NEXUS maps relationships between tasks using AI-powered semantic analysis and deterministic pattern matching. Nodes cluster by priority, namespace, and meaning. Tap to explore. Pinch to zoom. This is your second brain, visualized. — FOCUS MODE — Lock in. Select a task, set your session length, and enter a distraction-free countdown. Inspired by deep work methodology and Pomodoro technique. Your calendar can auto-block the time slot so nothing interrupts your flow. — OCR SCAN — Point your camera at a whiteboard, notebook, or printed page. The Vision engine extracts text instantly and drops it into a new task. Handwriting to queue in seconds. — VOICE INJECT — Speak your task aloud. Real-time speech recognition transcribes it directly into the task input. Hands-free productivity when you are on the move. — STREAK TRACKER — A GitHub-style contribution heat map on your home screen. Every completed task lights up the grid. Watch your streak grow. Stay accountable to yourself. — CALENDAR SYNC — Connect your calendar and block focused time automatically. VOID//TASK finds the next open slot and creates an event matched to your task estimate. — DEPLOY DASHBOARD — Ship your progress. Review completed work, audit your throughput, and track what you have accomplished across every namespace. — MULTI MODAL NOTES — Record audio over images, notes, sketches, overlays. — TEAM COLLABORATION — Share, import and export with your team. Export to AI. MD file export. Integrations with other productivity systems. — BUILT DIFFERENT — No ads. No tracking. No analytics. No accounts required. Your data stays on your device. Period. VOID//TASK is built with SwiftUI, SwiftData, and Apple Intelligence — fully native, fully private, fully yours. Integrations for GitHub, Slack, Notion, Google Calendar, Jira, and more are on the way. Welcome to the VOID. Your productivity starts here. Jack in. Privacy Policy: https://praxticusmobilelab.wixsite.com/void Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

OneCal4 screens
VOIDTASK4 screens

Verdict

The call

The clearest difference is update cadence: VOIDTASK at weekly against OneCal's monthly. VOIDTASK also leads on rating (5.0 vs 4.8). OneCal's advantage is ratings volume (19 vs 3) and iOS requirement (16.4 vs 18.5). On price, review sentiment, ads and in-app purchases 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. OneCal sells 6 in-app purchases, starting at $5.99 per month and VOIDTASK sells 1 in-app purchase, starting at $2.99 per month. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

VOIDTASK holds the better App Store score, 5.0 against 4.8. That said, the two scores are not equally well evidenced: OneCal has 19 ratings behind it against 3, so its average is the more settled of the two. Written reviews split almost evenly too, at 100% and 100% positive.

UpkeepUpdate frequency

OneCal ships an update monthly, VOIDTASK weekly. The most recent releases landed on November 5, 2026 and October 31, 2026 respectively.

Scorecard4 real differences · 6 level
OneCal versus VOIDTASK: the parameters behind the verdict, then further details
ParameterOneCalVOIDTASK
PriceFreeFree
Rating4.8 (19 ratings)5.0 (3 ratings) — better
Positive reviews100.0% of reviews100.0% of reviews
Number of ratings19 — better3
Update frequencyMonthlyWeekly — better
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, iPadiPhone, iPad
Requires iOS16.4 — better18.5
Further details — not scored
Size70 MB5 MB
Age rating4+4+
DeveloperOneCalPraxticus Mobile Labs LLC

Customer experience

OneCal

All ratings18 ratings
Positive94.4%
Neutral0.0%
Negative5.6%
Written reviews3 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

VOIDTASK

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews3 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

6 purchases

OneCal

Subscriptions6
  • Basic Monthly$5.991 Month
  • Essential Monthly$12.991 Month
  • Premium Monthly$29.991 Month
Show 3 more
  • Basic Yearly$59.991 Year
  • Essential Yearly$120.991 Year
  • Premium Yearly$300.001 Year
1 purchases

VOIDTASK

Subscriptions1
  • Integrations$2.991 Month

Questions

Is OneCal free?
OneCal is free to download, with in-app purchases available.
Is VOIDTASK free?
VOIDTASK is free to download, with in-app purchases available.
Which has better reviews, OneCal or VOIDTASK?
VOIDTASK is rated higher. OneCal averages 4.8 out of 5 from 19 ratings, while VOIDTASK averages 5.0 from 3 ratings.
Do OneCal or VOIDTASK have ads?
Neither OneCal nor VOIDTASK shows ads.
Which is updated more often, OneCal or VOIDTASK?
OneCal ships an update monthly, and VOIDTASK weekly. Most recently, OneCal was updated on November 5, 2026 and VOIDTASK on October 31, 2026.

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