I used PlanGrid and liked it, but it was a very limited tool, handy for punchlist and field notes markups.
Since then we have implemented NewForma v11, which I highly recommend, as it provides an organized and well-tracked method to record and respond to RFIs, PRs, including automatic transmittal creation, filing of all related email messages, project team management, and much more. It's not cheap, but depending on the amount of CA work you do, well worth it. NewForma interacts with MS Outlook automatically when you use it correctly with the plug-ins, and for most people, it's easy to learn.
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Haden Smith AIA
KWK Architects
Ballwin MO
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