Yes, I believe you can save the subscriber list onto your computer with both services. While moving subscribers from Mailchimp to Aweber was relatively straightforward, it did take me quite awhile to move all of my autoresponders and port my entire setup to Aweber. So if you can afford it, I would simply start out with Aweber and stay with them instead of having to move later.
As I was growing more and more frustrated with Infusionsoft I reached back out to Nathan to see how ConvertKit was doing. I wasn’t surprised to hear that they were experiencing constant growth month after month. New features were being added on a regular basis, and after a couple of side conversations with other users, I was happy to hear extremely positive reviews.
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I do agree that you should not build your business on free entirely. However, I also agree that if you are a small blogger or a non-profit organisation it is nice to save some money as you do not earn much. I’ve actually been using Mailerlite forever free plan until I’ve learned to comunicate with my audience and grown my business a bit to finally pay some money for newsletter service. You can check their quick comparison to MailChimp here: https://www.mailerlite.com/mailchimp-alternative That’s my personal alternative to MailChimp. Cheers!
Litmus recommends around 50 characters. Yes Lifecycle Marketing says emails with subject line up to 20 characters have ethe highest average open rate, unique click rate, and click-to-open rate. An analysis from Retention Science found that subject lines with 6 to 10 words results in the highest open rates. And Return Path advises using 61 to 70 characters.