Getting subscribers to your blog will help you build loyal visitors, get to know your readers better , strengthen the community around your blog, and also serve as a database.
There are multiple tools on the market for this. I use Benchmark Email, but you also have Mail Relay, Mailchimp, Acumbamail, GetResponse...
Aside from the price, when choosing a tool I recommend you check:
What variety of registration forms does it include.
What is the newsletter design and creation tool like?
If it offers A/B testing
The deliverability rate of emails.
The ease of sending autoresponders.
The analytics data it offers for newsletters: open rates, c level executive list time distribution, click map and distribution, etc.
Automation options.
However, to get blog subscribers, it won't be enough to install a subscription tool and forms: you'll also have to give them a reason to subscribe. No one (or almost no one) gives away their data for nothing, and the promise of sending blog updates isn't usually enough: you'll have to incorporate a "lead magnet ," an additional incentive in the form of free, quality content that you'll offer the reader in exchange for their email address: for example, an ebook, templates, a summary video, a mini-course, etc.