
ZoomInfo
Lusha
Hunter.io
Instantly.ai
lemlist
Clearbit
Snov.io
Apollo’s predictive prospecting, sales engagement, and actionable analytics help the teams to reach its full revenue potential.

Letterfork
Newsletter Guide
LetterWell
Repurpose
Newsletters by Refind
Typefully
Newsletter Crew
Resources for building, growing and monetizing a newsletter

Which is more popular?
Based on our record, Apollo.io seems to be more popular. It has been mentioned 69 times since March 2021.
Website, pricing, platforms and company facts side by side.
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| Website | apollo.io | letterstack.co |
| Pricing | — | |
| Company | Startup from the United States | — |
| Listed in |
What each product offers, as listed by its team.


Possible disadvantages
No features have been listed yet.
An editorial look at what each product does well and who it suits.


Overall verdict
Why this product is good
Recommended for
Overall verdict
Why this product is good
Recommended for
Walkthroughs and reviews on video.
Free software to find email addresses - apollo.io review
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Letterstack for iPhone
How often each product is chosen within a category, 0–100% relative to the other.


Share your experience with using Apollo.io and Letterstack. For example, how are they different and which one is better?
External articles and on-site reviews we used to compare the two products.


The right Apollo alternative fixes the part of Apollo that costs you meetings. Bad data calls for a better database, and a missing channel calls for a specialist tool next to Apollo.
What is the best AI prospecting tool for B2B sales in 2026? The best tool depends on your team's specific situation. toflow.ai is a strong fit for multi-channel outreach across email, LinkedIn, and WhatsApp, and is...
Apollo is a full sales engagement platform — sequences, email tracking, dialer, and a contact database. Their strength is email addresses, not phone numbers. Phone number coverage exists but it's thinner than...
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Recommendations tracked on public social media and blogs since March 2021.


Personal email domains destroy this. Clearbit's Enrichment API returns a null company when it hits gmail.com. Apollo routes personal domains straight to a consumer bucket and skips B2B fields entirely. Even PDL's /person/enrich endpoint... - Source: dev.to / 6 months ago
A few things worth flagging: PDL beats Clearbit's historical rates for US and Western European companies, but drops to ~52% match rate for Japan and South Korea specifically. Apollo underperforms on raw company matching but returns... - Source: dev.to / 6 months ago
One thing comparison guides consistently get wrong: Clay is not an enrichment API. It's a waterfall orchestration tool that calls People Data Labs, Apollo, Clearbit, and others in sequence for you. It's useful, but it adds 2–8 seconds of... - Source: dev.to / 6 months ago
Tracking Letterstack since Mar 2021.
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