I have used both, and I agree with your analysis. The great thing about MailChimp is that it lets you see the email in different clients. That is really the hardest thing about sending emails. However, you can use that service without doing everything else through MailChimp. Also, once you get the hang of it and develop templates, it no longer is much of an issue.
The disadvantage with using free services like Mailchimp is they’ll usually suspend your account without warning, it’s kind of like setting up a blog with wordpress.com or blogger.com. Since it’s a free service it’s kind of like they have this “one and your done” attitude which I guess is understandable since you’re getting the service for free, but sometimes I wonder. Now on to Aweber.
First of all you need to sign up for a free account at MailChimp. Here is the signup link (Aff. link). Once you have signed up, and logged into MailChimp dashboard, you will be seeing a screen similar to this, and click on create a list. The good thing about MailChimp dashboard is, it’s interactive, so you will not find any issues with getting started with it.

If Objective-C isn't your thing, their is Titanium from Appcelerator, you use JavaScript to build your app and it gets compiled into Objective-C. Mobile Tuts has a nice tutorial on how to consume the Twitter API, which is also REST based. It should give you a good foundation to get you started. (http://mobile.tutsplus.com/tutorials/appcelerator/appcelerator-using-json-to-build-a-twitter-client/)
“No, because a lot of others have told us those are the features within some of these all-in-one business solutions that make them extremely cumbersome and overwhelming. Our target customers are bloggers, podcasters and other people who are building audiences who want to be able to have an easy-to-use, but powerful email marketing system, with automation and all of the features that you want, without all of the things that you don’t need right now.”

Pop ups should be easy to close. Nothing is more annoying than having a pop up appear and you do not know how to close it. Sometimes your visitor may not be interested in what you have to offer and so will decline the offer by closing the pop up. If the ability to close the pop up is difficult, such as the exit link is not visible, you can lose visitors. Therefore make sure that your pop up can be easily closed to avoid losing readers.
So, when a new person signs up to your site (via your newly created signup box), they will (after confirming their subscription) start to receive the set of emails that you have setup.  You can create as many as you want and schedule them to be sent out at different intervals (i.e. 1 a day, 1 a week, 1 a day and then another one in a month’s time, etc.).
AWeber finds a healthy balance between ease of use and robust functionality. There are some nice features — particularly in the autoresponder realm — but navigation is intuitive enough that I was able to perform basic tasks without looking up tutorials. When I did find myself at a loss and turned to the online help resources, I was quite impressed with the range and scope of guidance available.
One thing I like most about MailChimp is it has a free pricing option whereas AWeber has $1 option as a starting point. That means you can create a free account on MailChimp without giving your credit card details whereas you need to pay $1 for first month to start using AWeber. You can try AWeber by just paying $1 for first month. After that, you need to pay $19 each month.
i know the benchmark, you can have 3 lists, all sent from 3 different companies, and if someone opts out, they get the choice if they are listed on other lists, to tick all the lists they are on, or just some. Does aweber and mailchimp do this? I have emailed mailchimp several times with the question but no answer yet, i am pretty sure they do not, so if someone opts out it is just an opt out from that list.
Pricing for InfusionSoft is also fairly different than AWeber. The interesting thing I discovered is that a lot of people—at least people who I spoke with—are hesitant to share how much they are billed. No one would tell me upfront, which led me to believe that Infusionsoft pricing depends on who you spoke with and what kind of deal you could get, and I was right.
Just so you know, I am quite a newbie to this brave new world of autoresponders.  Before I started this site (rather, I migrated from a previous platform to this self-hosted WordPress platform), I had not even heard of autoresponders.  But since the beginning of this site, I have adopted a new attitude: from a lackadaisical blogger to one more focussed on the possibility of building a long-term business.
Email marketing has the highest conversion rates of any marketing channel. In fact, sixty-six percent of online consumers made a purchase after receiving an email marketing message — which is more than social and direct mail, according to the Data & Marketing Association. And transactions from email are three times more profitable than those made on social media, reports the global management consulting firm McKinsey & Company.