Slack

Slack is the company chat tool you'll probably end up on, whether you wanted to or not. The category is so dominated by Slack that arguing for Microsoft Teams (free with Microsoft 365 if you have that) or Discord (great for community, weird for company) feels like swimming upstream. For most startups it's just the path of least resistance. The product itself is fine. Channels, DMs, threads, voice/video huddles, integrations with literally everything (GitHub, Linear, Notion, Vercel, Stripe, etc). The mobile app works. Search is OK. Recent additions like Slack Lists (lightweight tasks) and Slack AI ($10/user/month add-on for summaries and Q&A) are useful if you'll actually use them, easy to ignore if you won't. My honest advice for early-stage founders: delay adding Slack as long as you can. While you're 1-3 people, just use texts, WhatsApp, or email. Slack is great at making async work feel productive while actually being its own form of distraction. The 'someone might message me right now' anxiety is real. Once you're 5+ people and need formal channels, Slack is the obvious choice. The free tier got worse in 2022. Message history is now limited to 90 days, which is barely enough for any kind of historical reference. You're going to be on Pro ($8.75/user/month) the moment you care about searching what you said three months ago. Where Slack genuinely wins: huddles (impromptu voice/video, no link needed) are great for quick syncs. The integration depth is unmatched. Custom emoji culture is real and increases team cohesion in surprising ways. Slack apps you build internally can replace whole tools (a bot that handles deploy approvals, a slash command that creates Linear tickets). If you're already on Slack, fine. Keep going. If you're starting a company and you're under 5 people, hold off. Use WhatsApp groups or text. You don't need Slack until you have enough people that ad-hoc messaging breaks down.