Kalender Sync vs Slashy: Features, Pricing & Which Is Better (2026)

A side-by-side comparison of Kalender Sync and Slashy — features, pricing, and ideal use cases — to help you decide which AI tool fits your workflow.

Kalender Sync

PPJ Venture Labs UG

Freemium

GDPR-compliant calendar sync that links Outlook, Google, iCloud and more, and lets Claude, ChatGPT or other agents manage your calendars via MCP.

Multi-Provider Calendar Sync: Connects Outlook, Google, Apple iCloud, GMX, WEB.DE, mailbox.org, kSuite, Posteo and STRATO calendars in real time, one-way or two-way.
Visibility Levels: Choose per sync whether the target sees busy only, title and time, or full event details.
AI Assistant Access via MCP: Remote MCP server lets Claude, ChatGPT, Codex, Cursor, Grok and OpenClaw read and manage your calendars.
Agent-Driven Setup: Ask your connected AI agent to create syncs, find free time across calendars and schedule events.
Per-Calendar Permissions: Grant AI access calendar by calendar, with optional write access and an access log.
Calendar Sharing: Share a calendar with another person without exposing the underlying account.
Credit-Based AI Usage: Monthly AI credits cover event searches, availability checks and event edits, with optional top-ups.
GDPR Compliance: Hosted in Germany with data-protection-focused design.

A freelancer mirrors client calendars into one personal calendar while hiding event details behind busy blocks.
A manager with several roles keeps Outlook, Google and iCloud calendars synchronized to avoid double bookings.
A tax advisor lets Claude find free slots across work and private calendars and book appointments.
A coach shares availability with clients without giving access to the full calendar.
A developer connects Claude Code or Cursor to their calendar through MCP to plan the week.
An interim manager with multiple companies consolidates every company calendar into a single view.

Paid

Slashy is an AI-native email client that drafts replies in your voice, triages what matters, and makes sure no follow-up slips through.

AI Reply Drafting: Drafts email replies in your own voice so you can review and send in seconds.
Smart Triage: Automatically surfaces the emails that matter and filters out inbox noise.
Follow-up Tracking: Tracks pending conversations so no follow-up slips through the cracks.
AI-Native Inbox: A redesigned email client built around AI rather than added onto an old one.
Enterprise Controls: SSO, SCIM, and customized security controls for teams on the Enterprise plan.

Clearing a Busy Inbox: Triage and respond to high volumes of email in a fraction of the usual time.
Consistent Voice Replies: Draft on-brand responses that sound like you without writing from scratch.
Never Missing Follow-ups: Stay on top of threads that need a reply or a nudge.
Team Email at Scale: Roll out an AI email client across an organization with SSO and SCIM.