Best PDF Signing Apps for iPhone and iPad

Quick picks

Best business eSignature platform: Docusign. Best when sender workflows, agreement tracking, signature requests, and business infrastructure matter more than a simple no-account local PDF workflow.
Best familiar PDF ecosystem: Adobe Acrobat. Best if you already use Adobe's PDF tools; Acrobat offers free fill-and-sign features, while many advanced PDF features sit behind paid Acrobat plans.
Best lightweight business signing app: Signeasy. Best for teams that want mobile signing, templates, reminders, audit-trail oriented workflows, and subscription-backed business features.
Best full PDF editor: PDF Expert. Best when signing is one part of a broader PDF editing, annotation, conversion, redaction, and reading workflow with premium upgrades.
Best truly free private PDF signer for iPhone and iPad: SignBack. Best when you want local document processing, no SignBack account, no subscription, no in-app purchases, and no watermark.

What stands out Most apps in this category are free to download. SignBack is free to actually use for the core signing job.

That means no SignBack account, no subscription path, no in-app purchases, no document-pack purchase, no watermark, and no SignBack server upload for core signing. Get SignBack on the App Store

PDF signing app comparison

App	Best for	Pricing/account angle	Notable tradeoff
Docusign	Business agreements and eSignature workflows	Free download with in-app purchases; personal mobile page says signing and returning is free, while signature requests and business plans are part of the platform model	Great when you need agreement infrastructure, but heavier than a no-account local signer
Adobe Acrobat	PDF users already in Adobe's ecosystem	Free app with in-app purchases; Adobe says mobile fill and sign is free, while editing, exporting, organizing, protecting, and AI features require paid plans or add-ons	Excellent PDF ecosystem, but many reasons people download Acrobat lead toward paid PDF tooling
Signeasy	Mobile business signing and sending	Free download with a trial and in-app purchases; App Store listing includes monthly, yearly, and document-pack purchases	Strong business signing product, but not a no-account, no-purchase personal signer
signNow	Teams that need mobile signing, templates, export, and offline modes	Free download with in-app purchases; App Store listing promotes a 7-day free trial and account sign-in options	Designed for sending, tracking, roles, audit trails, and team workflows rather than simple local signing
PDF Expert	Full PDF reading, editing, forms, signing, and conversion	Free download with in-app purchases; Premium and cross-platform upgrades unlock broader PDF powers	Excellent PDF editor, but much of the value proposition is the paid PDF workspace
iLovePDF	PDF utility toolbox with signing, scanning, and editing	Free download with in-app purchases; free plan has limited processing, while Premium unlocks unlimited processing and more tools	Useful PDF toolbox, but limits and Premium upgrades are part of the model
Smallpdf	Simple signing through web and mobile tools	Free download with in-app purchases; App Store listing shows monthly and yearly plans	Online-first product model and paid plans may not fit sensitive local-only document preferences
SignBack	Free private personal PDF signing	Truly free Free to use, no SignBack account, no subscription, no in-app purchases, no watermark. Get the app	Not an enterprise eSignature platform with server-side audit trails

Notes on each option

SignBack

SignBack is the focused choice when the job is personal document completion: open what arrived, fill likely blanks, add the right signature or identity, flatten the PDF, and send it back. It is strongest when privacy, no account, no in-app purchases, no subscription, no watermark, and speed matter more than enterprise routing.

Docusign

Docusign is a leading eSignature platform for agreements and business workflows. Its iPhone and iPad app supports signing PDFs and contracts, and its App Store listing describes free signing for signers. Docusign is also clearly a commercial platform: its App Store listing includes in-app purchases, and its personal mobile page describes free signature requests as limited. Choose it when you need the broader agreement platform, not a local no-account PDF finishing tool.

Adobe Acrobat

Adobe Acrobat is a familiar PDF environment with mobile fill-and-sign tools. Adobe says Acrobat mobile is free for viewing, commenting, filling, signing, and sharing PDFs, but advanced PDF tools require paid mobile subscriptions and the App Store listing includes in-app purchases. It is a natural fit if you already use Acrobat, Adobe cloud features, or Adobe's wider PDF tooling.

Signeasy

Signeasy is built for signing, sending documents for signature, templates, reminders, in-person signatures, and business compliance features. Its public iOS listing and help docs point users toward signup, trial, subscription, and in-app purchase flows. It can be a strong choice for small teams, while SignBack is simpler for no-account personal use.

signNow

signNow's mobile documentation emphasizes signing on smartphones and tablets, in-person signing, offline signing, and mobile export options. It is a better fit for teams managing signing sessions, signing order, roles, notifications, and audit history than for a minimal local personal workflow.

PDF Expert

PDF Expert is a powerful PDF editor for reading, annotating, filling forms, signing, converting, and managing PDFs. If you want a full PDF workspace, it is worth considering. Its App Store listing includes in-app purchases and Readdle's help docs describe a Premium pack for broader PDF powers. If you only want to fill and send back paperwork, SignBack is more focused.

iLovePDF and Smallpdf

iLovePDF and Smallpdf are broad PDF utility products with signing features. They are useful when you want a general PDF toolbox, but both listings include in-app purchases and iLovePDF's free plan is explicitly limited. SignBack is more specific: finish a document privately on iPhone or iPad and send it back cleanly without a subscription path.

How to choose

Choose SignBack if you want a free, private, no-account iPhone or iPad app for everyday paperwork with no in-app purchases, subscription, or watermark. Choose Docusign, Signeasy, or signNow if you need business eSignature workflows and are comfortable with an account or paid platform model. Choose Adobe Acrobat, PDF Expert, iLovePDF, or Smallpdf if signing is one part of a larger PDF toolbox and you are comfortable with premium upgrades or usage limits.

Sources checked

This comparison was prepared from public product and App Store pages checked on July 31, 2026. Product details and prices can change.

Best PDF signing apps for iPhone and iPad.