Based on our record, Email List Verify seems to be more popular. It has been mentiond 2 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
If you're not getting the right email addresses from ContactOut and it's bouncing back, you could always run the email addresses through something like emaillistverify.com to make sure they're valid before you try to email them. (you should do that always anyway to protect your email deliverability). Source: almost 2 years ago
Emaillistverify.com is the service I use. Source: almost 2 years ago
NeverBounce - Real-time email verification and cleaning to ensure emails never bounce.
Captain Verify - Captain Verify is the best solution to Verify & Clean the validity of your emails.
ZeroBounce - Removes invalid emails from your list to prevent email bounces from ruining your deliverability.
CampaignKit - Email Validation for marketers. Detect invalid and malicious email addresses in your email lists.
Email Verifier - Email verifier app lets you verify email.
ListClean - Get rid of invalid, abuse & spam-trap from your email list.