Adobe's Fill & Sign tool does not use AI to complete forms for you — it detects where the fields are and leaves you to type every value. That's the gap people are usually looking for when they search "Adobe Fill and Sign AI". Acrobat is a full PDF editor where filling is one feature among many; Filly AI does one thing — getting forms filled and signed — and automates the retyping Acrobat leaves to you. The comparison also matters more than it used to: Adobe retired the standalone Fill & Sign mobile app in 2025, folding it into Acrobat Reader Mobile, so anyone searching for it today needs to know both what changed and what still fills forms the way they expect.
Choose Adobe Acrobat if you need to edit PDFs — rearrange pages, redact, convert formats — and only occasionally fill a form by typing into it. Choose Filly AI if you fill forms repeatedly: it uses AI to detect fields on any PDF or Word file (including scans, via OCR), auto-fills them from saved client profiles, batch-fills one form for many people, and sends no-login e-sign links. Filly has a free plan (10 fills/month); paid plans start at $19/month.
Is Adobe Fill and Sign discontinued?
The standalone Fill & Sign mobile app is retired. Adobe's own migration notice confirms the mobile app was folded into Acrobat Reader Mobile in 2025, and Adobe now directs Fill & Sign users to that app. The desktop and web "Fill & Sign" tool inside Acrobat is unaffected — it's specifically the separate mobile app that no longer exists on its own. If a bookmark, old app-store listing, or saved shortcut still points at the standalone app, that's why it's gone: it was merged, not shut down entirely.
Does Adobe Fill and Sign use AI to fill forms?
Not in the way most people mean when they search for it. Acrobat's Fill & Sign auto-detects where the fields are on a PDF and offers to reuse values you've typed before, but you still supply every value and place your signature yourself — it doesn't read a form and complete it from data it holds about your clients. The detection is layout analysis, not an AI that knows what the form is asking for.
Part of the confusion is that Adobe has put the word "AI" on several Acrobat surfaces in the last two years, and they are three different features doing three different jobs. Knowing which one you're reaching for saves a lot of disappointment on a stack of forms:
- AI Assistant — reads and explains a document. Does not fill fields.
- Auto-Complete — fills fields, but from values you personally typed before on that machine. Not AI.
- Prepare Form — detects where fields should go so you can create a fillable form. Field creation, not completion.
None of the three fills a form from a stored record of a specific client, which is the thing people are actually searching for.
What does Acrobat's AI Assistant actually do?
Adobe documents AI Assistant as a comprehension tool. You open a document and ask it questions; it answers from the text and points you at the passage it used. That is genuinely useful when a 60-page contract lands in your inbox and you need to know what the termination clause says. It is a paid add-on rather than part of the base Acrobat subscription — see Adobe's own AI Assistant page for the current capability list, which changes.
What that means practically: AI Assistant helps you understand a form. It is not the thing that puts your client's date of birth into box 14.
So which feature actually fills the fields?
That's Auto-Complete, and no. Acrobat keeps a local list of values you have typed into form fields before and offers them back as you tab through a new form. Type your own address into fifteen forms and the sixteenth will suggest it. Adobe's help page describes it as a personal autofill collection stored on your machine.
The design assumption underneath it is that you are filling forms about yourself. That works for a freelancer signing their own W-9. It breaks the moment you are a paralegal, bookkeeper, HR coordinator, or agency operator filling the same form for the fortieth different person, because there is no notion of "which person" — just a pool of everything anyone ever typed on that computer.
What about the AI that detects form fields?
This is the third feature and the one most often mistaken for the other two. Acrobat's Prepare Form tool scans a document and guesses where the fields should go, so you can turn a flat, non-interactive PDF into a fillable one. That is field creation, not field completion — you end up with an empty fillable form and still have to type into it.
It's worth separating those two problems, because tools solve one or the other and rarely both. If your file won't let you type at all, you have a field-detection problem. If it lets you type but you're typing the same information for the hundredth time, you have a data problem.
What's the core difference?
Acrobat's Fill & Sign is manual: you click each field and type. That's fine for one form, but small businesses already spend roughly 16 hours a week on administrative tasks, and UK research by Sage found admin consumes so much time that small firms effectively work a 13th month each year. Filly AI attacks exactly that: it reads the form once, then fills it from a profile so the same name, address, and details never get typed twice.
Put structurally, useful AI form filling has three parts, and any tool claiming to do it should be judged on whether it has all three:
- Reading the form. Working out what each field is asking for from the label text next to it — including on flat and scanned documents where there are no fields to read, only lines and boxes.
- Holding the answers. A record per person, not per machine. "Fill this for Maria Delgado" has to mean something.
- Matching one to the other. Deciding that a box labelled "Surname (Family name)" wants the same value as one labelled "Last name" on a different form.
Acrobat has a version of the first. It doesn't have the second, so the third has nowhere to point.
Filly AI vs Adobe Acrobat: feature comparison
| Feature | Filly AI | Adobe Acrobat |
|---|---|---|
| AI field detection on any PDF/Word file | Yes — including scanned forms via OCR | Auto-detects fields on some PDFs; manual placement otherwise |
| Auto-fill from saved profiles | Yes — reusable client profiles | No — each form is typed by hand |
| Batch fill (one form, many clients) | Yes | No |
| E-signature | No-login link; recipient signs in the browser | Yes, via Acrobat Sign (separate limits by plan) |
| PDF editing (pages, redaction, conversion) | No — filling and signing only | Yes — industry standard |
| Free plan | Yes — 10 fills/month, no credit card | Limited free web tools; apps are paid |
| Starting paid price | $19/month | From about $12.99/month (Standard, annual) |
| Install required | No — runs in the browser | Desktop apps for full features; web version available |
When is Adobe Acrobat the better choice?
If your work is about the PDF itself — combining files, editing text inside a document, redacting, converting Word to PDF and back — Acrobat is the right tool. (Filly does cover the common cases free in the browser: merging, redacting SSNs and personal details, and Word-to-PDF conversion — but it is a form filler, not a PDF editor.) It's the most complete PDF editor available, and its Fill & Sign feature is perfectly serviceable for the occasional form.
When is Filly AI the better choice?
If you fill the same kinds of forms for different people — client intake, government forms, contracts, invoices — the manual approach doesn't scale. With Filly you save each client's details once, then any uploaded form fills itself; a batch fill produces one completed document per client in a single run. Signature collection matters too: industry data shows about 79% of e-signed agreements complete within 24 hours, and roughly half within 15 minutes — compared to days for print-and-scan.
Can you use both?
Yes, and many people do: Acrobat to prepare or edit the document, Filly to fill and send it. They overlap only at the filling step — and that's the step Filly automates. Try it on one of the ready-made form templates or upload your own PDF.
Frequently asked questions
Is Filly AI a replacement for Adobe Acrobat?
Only for form filling and signing. Filly doesn't edit PDFs — no page rearranging, redaction, or format conversion. If filling forms is the part of your PDF work that eats time, it replaces that part.
Does Filly AI handle forms that aren't fillable PDFs?
Yes. Scanned or flat PDFs are read with OCR and AI places your values onto the page. Word documents are supported too, and export in their original format.
Which is cheaper?
Acrobat Standard starts lower (about $12.99/month billed annually) but fills forms manually. Filly starts at $19/month — and has a genuinely free tier (10 fills/month) — but each fill is automated, so the comparison depends on how many forms you complete. See Filly's pricing.
Do recipients need an account to sign?
With Filly, no — they open a link and sign in the browser. Acrobat Sign recipients also don't need an account, but sending limits depend on your Acrobat plan.
What replaced the Adobe Fill and Sign app?
Acrobat Reader Mobile. Adobe merged the standalone Fill & Sign mobile app into Acrobat Reader Mobile in 2025, so the same fill-and-sign capability is there, just inside the main Acrobat app rather than a separate download. If you want auto-fill from saved profiles and batch fill rather than typing each field by hand, that's the gap Filly fills.
What is the best Adobe Fill & Sign alternative?
It depends which part you're replacing. For general PDF editing, another full editor is the closer match. For people who fill the same kinds of forms repeatedly, Filly AI is the stronger fit: its AI reads the form and auto-fills it from saved client profiles, batch-fills for up to 20 clients at once, and includes no-login e-signature — with a free plan and no Acrobat subscription.
Is Adobe Acrobat AI Assistant included in my Acrobat subscription?
No — Adobe sells it as a separate add-on on top of Acrobat Standard or Pro. Check Adobe's pricing page for current terms, as they have changed more than once.
Does Acrobat's auto-fill sync between my computers?
The Auto-Complete list is stored locally, so entries typed on your laptop aren't offered on your desktop. That's a privacy-sensible default and an operational nuisance if you work across machines. Filly's profiles live in your account, so any device you sign in on fills the same way.
Why does Acrobat suggest the wrong value in a field?
Because Auto-Complete matches on what you typed into similarly-named fields before, with no understanding of context. Two forms both labelled "Name" — one wanting the applicant, one wanting the employer — pull from the same pool.
Can Acrobat fill a PDF from an Excel spreadsheet?
Not natively in the desktop app. Merging a spreadsheet into many copies of a form is a data-merge job Acrobat leaves to scripting or third-party tools. Our guide to batch filling from a spreadsheet covers the options.
Can AI be trusted to fill a legal or government form?
Only with a human review step. Any tool that fills a form should show you every value it placed and where it placed it before you export or sign. Treat an unreviewed auto-filled government form the way you'd treat one a new assistant filled on their first day — which is why Filly puts a review screen between the fill and the export.
Do I need an Adobe Acrobat subscription to use Filly?
No. Filly is completely standalone — upload any PDF or Word file, review the AI-filled result, then export, share, or e-sign. No Acrobat Pro or Adobe account required. Filly starts free (10 fills a month, no card) with paid plans from $19/month.