You have a few options for this these days - which one you choose will depend on your own requirements and flexibility demands. The most "officially" supported and old-school way to deal with it is to simply have a Related Action users can click which will take them into a process that handles comment entry. This obviously isn't quite as seamless or click-minimized as what you seem to be asking for. These we have both a!startProcess() and a!writeToDataStoreEntity(), which you could use one of in this case - either use the former to start a process when the user clicks something, which writes their entered comment; or use the latter to just write it straight to the DB. Using StartProcess is the approach recommended by a lot of folks around here because it leaves behind a traceable process history when it comes time to troubleshoot/debug. Speed-wise I'd guesstimate that both approaches are similar - unless you've done something explicitly inefficient, the user should experience a near-instant result in both cases.