The short version
Spark is the multi-account client. Inbox Hero is an AI that files the noise, drafts your replies, answers questions about your mail, and quarantines phishing — for one flat $10/mo (or $99/yr) after a 30-day free trial. If you want an inbox that runs itself (and a built-in security layer), Inbox Hero wins; if you specifically want multi-account client, Spark is worth a look.
Feature-by-feature
| Inbox Hero | Spark | |
|---|---|---|
| Continuous AI auto-filing | ✓ | Grouping |
| Drafts replies in your voice | ✓ | Premium |
| Ask your inbox in plain English | ✓ | Partial |
| Fraud & phishing quarantine | ✓ | ✗ |
| Works inside existing Gmail | ✓ | New client |
| Learns from your corrections | ✓ | ✗ |
Where Spark is a fine choice
Spark is a polished email client with a Smart Inbox and broad provider support. It's a solid free-to-cheap option — but the useful AI is gated to premium, and it's a client you adopt rather than an AI that runs your existing inbox for you.
Where Inbox Hero pulls ahead
- Another client to adopt across your devices.
- AI drafting and advanced features are gated to premium tiers.
- No fraud/phishing quarantine.
- Smart Inbox groups mail; it doesn't continuously file the noise out the way AI triage does.
On top of that, Inbox Hero adds capabilities most tools in this space simply don't have — an AI you can ask about your inbox, replies drafted in your voice, and a Fraud folder that intercepts phishing and malware.
Frequently asked questions
Is Inbox Hero better than Spark?
For hands-off triage plus AI drafting, inbox Q&A, and phishing protection at one flat $10/mo (or $99/yr) after a 30-day free trial, Inbox Hero offers more in a single product. Spark ($5–$8/mo) is a good fit if you specifically want multi-account client.
How much do Inbox Hero and Spark cost?
Inbox Hero is free for 30 days ($0 today), then $10/month ($5 per extra mailbox) with everything included. Spark costs $5–$8/mo.
Can Inbox Hero and Spark both connect to Gmail?
Yes, both work with Gmail. Inbox Hero also connects to iCloud, Yahoo, Fastmail and other IMAP mailboxes, and layers onto your existing inbox rather than replacing it.
Take back your inbox today
Connect Gmail or any mailbox in one click. Inbox Hero files the noise, drafts your replies, and quarantines phishing. It is free for 30 days ($0 today).
Get started free