We use Phreesia in our office. We have been with them since 2014. They are really good at what they do. If I ever change EHR's, my rule is that they must interface with Phreesia.
But... technically, AC and Phreesia no longer work with each other. Which is kind of odd. Because I started using Phreesia because of a big advertising push by AC. But at some point in 2016ish, they had a bad break up.
That being said, both IT teams know that I like both softwares. And they have continued to service issues that come up. But if I ask for upgrades to the interface, (Billing info is not transferred after the move to TLS 1.2) they say, "sorry, we don't support AC" so we are not going to spend a significant amount of time to add that."

But, they do keep me running. And that I am happy with.
Check in is on a Phreesia supplied pad. or a Kiosk (which I don't use)
They have mobile check in available to, up to 24hrs before they even show up.
E&B is run during their check in time on the pad.
Benefits and deductible are all clearly stated.
A .pdf of the entire check-in interview is auto created, that my team stores in the chart.
Screenings can be done and scored on the pad. (we use the MCHAT and Edinberg)
Phreeisa is also my main merchant point with 98% of my transactions passing through it for all business.
We just signed up for "Payment Assurance", which basically charges the card on file for balances due automatically at a time you specify. (requires manual uploading a .CSV, we do this upload at the same time as sending billing e-statements.) But no more chasing balances, and no more remembering to charge a card after 30days.
I really like them. Not sure what I would use instead of them. In fact, we would much rather change EHRs than lose Phreesia. Honestly they are that good at what they do. It's not to say they don't have issues and things that need fixed, all IT solutions will do that.
But the catch about "not supporting AC" may be a talking point for you. They have a handful of AC users. And since the interface technically exists, because I'm using it, they would probably have you. If you have any more questions. Let me know.
It flows like this, A patient on the AC schedule auto populates on the Phreesia dashboard.
When that patient shows up, front desk pick up a pad, selects type of interview (ie. Well Check, Sick Visit...) and hands it to the patient. Also quickly scans the pt insurance card and ID.
A status bar on the Phreesia dashboard tells my nurses exactly who is checking in and that pt's progress. When they drop down to the "checked in" portion, my nurses get up and go ask for that person and room them almost immediately.
The front desk then pushes cntrl-F11 (AC shortcut) on the keyboard to import a .HL7 file from that check-in. they also then file the .PDF report from Phreesia in AC so that the Provider can see any results they need from it.
If a balance is due and loaded, the pt is prompted to pay it during check-in. We do up-front billing, so on they way out, the front desk will collect any balances due for that day based on the E&B Phreesia provided.
That's it. Check in for the team is less than 5 mins of work. The pt usually has the pad longer than my team works on checking them in.
For reference, we see about 30-40 patients a day with 1 front desk person and 2 nurses.
Nic