These three products all say "CPD" on the tin and record three different things. GPAtlas's CPD Hub captures learning activity inside its ecosystem. FourteenFish runs the appraisal process itself. iatroX measures learning: baseline, error, remediation, reassessment, retention. Treating them as substitutes produces either redundant subscriptions or evidential gaps; treating them as layers produces a rather complete system. Here is each layer on its own terms.
Layer one: activity capture
The GPAtlas CPD Hub records learning within the GPAtlas ecosystem, topics read, audio completed, cases practised, questions asked, and produces records and certificates, with the Portfolio & Appraisal Hub helping turn rough notes into structured, portfolio-mapped reflections. This is the same evidential function GPnotebook Pro performs over its reference library, tracking pages, video, podcast and quiz activity into an exportable statement: honest, useful documentation that learning activity occurred, generated with near-zero friction from work you were doing anyway. Its inherent limit is the limit of all activity capture: it witnesses engagement and is silent on what changed in your head. A capture layer with reflection attached is legitimate CPD; it is the floor of the evidence, not the ceiling.
Layer two: the appraisal system of record
FourteenFish records something categorically different: the appraisal itself. The current NHS England template, supporting information organised into it, MSF and patient feedback surveys, the appraiser workflow, sign-off, the revalidation trail. No learning platform replaces this layer, and FourteenFish does not attempt the layers around it: it stores what you bring. Its capture conveniences, the apps, email-to-diary, exist precisely because the system of record depends on being fed, and the practical question for everything else in your stack is simply how cleanly it feeds this layer, whether directly, by export, or by email.
Layer three: measured learning
iatroX records the object neither of the others produces: the learning event itself, measured. A session establishes baseline performance on a topic; errors are logged specifically, with the Socratic Tutor's dialogue naming the misconception and its correction against guidance cited into NICE, CKS, SIGN and SmPC sources; immediate reassessment shows the correction took; a delayed retest weeks later shows it held; and My CPD binds the sequence to your own reflection and attestation. This is the layer where evidence stops describing activity and starts demonstrating change: a scored, remediated and retested learning record demonstrates more than a certificate of attendance alone. Its deliberate limit mirrors the others': it is not a portfolio of your feedback and significant events, and not an appraisal workflow; it produces the strongest class of learning entry and hands it upward.
The conclusion the comparison actually supports
Different evidential functions, not competing products. A GP could sensibly run all three: GPAtlas capturing the reading-and-listening layer with structured reflections, iatroX generating the assessed spine, FourteenFish holding the appraisal of record, and each record filed once, in the right layer. Equally sensibly, a GP could run two, or substitute within a layer, BMJ Portfolio now covers general capture free, GPnotebook Pro captures reference reading, our fuller comparison of that pairing is at /blog/gpnotebook-pro-vs-iatrox-cpd. What does not work is expecting any single layer to make the other two's claims: capture cannot prove learning, measurement cannot run your appraisal, and the appraisal system proves nothing by itself about what you know.
A one-paragraph buying guide
Start from the layer you are missing. If your portfolio is empty because logging is friction, buy capture, GPAtlas if you want its learning ecosystem attached, or use the free general options. If appraisal administration is the pain, the system of record is the purchase, and for most GPs that decision was made years ago. If your file is thick with certificates and thin on demonstrated learning, which is the commonest gap current guidance highlights, the measurement layer is the one that changes what your portfolio can claim.
Frequently asked questions
Can GPAtlas's certificates go into FourteenFish?
Yes, as with any provider's certificates: exported or emailed into the diary as supporting information, with your reflection attached. The capture layer's whole job is producing artefacts the system of record accepts.
Does iatroX duplicate what the CPD Hub records?
Only if you file the same session twice. The clean pattern: activity evidence for input you did in GPAtlas, assessed records for iatroX sessions, one entry per learning cycle in whichever form is strongest.
Which layer matters most at appraisal?
The appraisal happens in layer two regardless. What distinguishes a portfolio is layer three's presence: a few entries that demonstrate measured, corrected, retained learning among the certificates. Appraisers see capture constantly and measurement rarely.
Where does BMJ Portfolio fit in this three-layer picture?
Squarely in layer one, as a free, provider-agnostic capture-and-storage layer with AI reflection support, and its direct FourteenFish integration is exactly a layer-one-to-layer-two pipe. Its arrival strengthens the argument of this article: capture is becoming free and commoditised, the appraisal system of record remains its own category, and measured learning stays the scarce layer that changes what a portfolio can claim.