{"id":390,"date":"2017-04-05T06:10:01","date_gmt":"2017-04-05T06:10:01","guid":{"rendered":"http:\/\/inwizards.com\/blog\/?p=390"},"modified":"2026-01-02T14:15:06","modified_gmt":"2026-01-02T14:15:06","slug":"draw-digital-signature-ios-using-swift-2-0","status":"publish","type":"post","link":"https:\/\/www.inwizards.com\/blog\/draw-digital-signature-ios-using-swift-2-0\/","title":{"rendered":"How to Draw Digital Signatures in iOS Using Swift 5: A Developer\u2019s Tutorial"},"content":{"rendered":"

Digital signatures are essential for mobile apps that handle contracts, forms, or approvals. Whether you\u2019re building a banking app, a document management system, or a delivery app, enabling users to sign directly on their device enhances usability and compliance. In this tutorial, we\u2019ll show you how to implement digital signature capture in iOS using Swift 5<\/b>, step by step.<\/p>\n

Table of Contents<\/b><\/h2>\n
    \n
  1. Why Digital Signatures Matter<\/li>\n
  2. Project Setup in Xcode<\/li>\n
  3. Creating a Signature View<\/li>\n
  4. Integrating the Signature View in Your ViewController<\/li>\n
  5. Saving Signatures to Photos or PDF<\/li>\n
  6. Testing and Debugging<\/li>\n
  7. FAQs<\/li>\n<\/ol>\n

    Why Digital Signatures Matter<\/b><\/h3>\n

    Digital signatures improve workflows by:<\/p>\n

      \n
    • Eliminating the need for printing, signing, and scanning.<\/li>\n
    • Reducing errors in document handling.<\/li>\n
    • Increasing trust and compliance in mobile forms.<\/li>\n<\/ul>\n

      In iOS, capturing a signature is straightforward using UIView for drawing, combined with UIImage for saving the results.<\/p>\n

      Project Setup in Xcode<\/b><\/h3>\n
        \n
      1. Open Xcode<\/b> and create a new project.\n
          \n
        • Template: App<\/b><\/li>\n
        • Language: Swift<\/b><\/li>\n
        • Interface: Storyboard<\/b><\/li>\n<\/ul>\n<\/li>\n
        • Name your project, e.g., DigitalSignatureDemo.<\/li>\n
        • Ensure you select iOS 14+<\/b> or later for modern Swift compatibility.<\/li>\n<\/ol>\n

          Creating a Signature View<\/b><\/h3>\n

          We’ll create a custom UIView that tracks touches to draw a signature.<\/p>\n

          Step 1: Create a Swift file<\/b><\/h4>\n
            \n
          1. Go to File \u2192 New \u2192 File \u2192 Swift File<\/b><\/li>\n
          2. Name it SignatureView.swift.<\/li>\n<\/ol>\n

            Step 2: Implement the drawing logic<\/b><\/h4>\n

            import UIKit<\/p>\n

             <\/p>\n

            class SignatureView: UIView {<\/p>\n

             <\/p>\n

            private var lines: [Line] = []<\/p>\n

            private var strokeColor: UIColor = .black<\/p>\n

            private var lineWidth: CGFloat = 2.0<\/p>\n

             <\/p>\n

            required init?(coder: NSCoder) {<\/p>\n

            super.init(coder: coder)<\/p>\n

            self.backgroundColor = .white<\/p>\n

            }<\/p>\n

             <\/p>\n

            override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {<\/p>\n

            guard let touch = touches.first else { return }<\/p>\n

            let newLine = Line(points: [touch.location(in: self)], color: strokeColor, width: lineWidth)<\/p>\n

            lines.append(newLine)<\/p>\n

            setNeedsDisplay()<\/p>\n

            }<\/p>\n

             <\/p>\n

            override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {<\/p>\n

            guard let touch = touches.first, var lastLine = lines.popLast() else { return }<\/p>\n

            lastLine.points.append(touch.location(in: self))<\/p>\n

            lines.append(lastLine)<\/p>\n

            setNeedsDisplay()<\/p>\n

            }<\/p>\n

             <\/p>\n

            override func draw(_ rect: CGRect) {<\/p>\n

            super.draw(rect)<\/p>\n

            guard let context = UIGraphicsGetCurrentContext() else { return }<\/p>\n

            context.setLineCap(.round)<\/p>\n

             <\/p>\n

            for line in lines {<\/p>\n

            context.setStrokeColor(line.color.cgColor)<\/p>\n

            context.setLineWidth(line.width)<\/p>\n

            for (i, point) in line.points.enumerated() {<\/p>\n

            if i == 0 { context.move(to: point) }<\/p>\n

            else { context.addLine(to: point) }<\/p>\n

            }<\/p>\n

            context.strokePath()<\/p>\n

            }<\/p>\n

            }<\/p>\n

             <\/p>\n

            func clear() {<\/p>\n

            lines.removeAll()<\/p>\n

            setNeedsDisplay()<\/p>\n

            }<\/p>\n

             <\/p>\n

            func getSignatureImage() -> UIImage {<\/p>\n

            UIGraphicsBeginImageContextWithOptions(bounds.size, false, 0)<\/p>\n

            drawHierarchy(in: bounds, afterScreenUpdates: true)<\/p>\n

            let signature = UIGraphicsGetImageFromCurrentImageContext()!<\/p>\n

            UIGraphicsEndImageContext()<\/p>\n

            return signature<\/p>\n

            }<\/p>\n

            }<\/p>\n

             <\/p>\n

            \/\/ Helper struct<\/p>\n

            struct Line {<\/p>\n

            var points: [CGPoint]<\/p>\n

            var color: UIColor<\/p>\n

            var width: CGFloat<\/p>\n

            }<\/p>\n

             <\/p>\n

            Integrating the Signature View in Your ViewController<\/b><\/h3>\n
              \n
            1. Open Main.storyboard<\/b> and add a UIView.<\/li>\n
            2. Set its class to SignatureView in the Identity Inspector.<\/li>\n
            3. Add two UIButtons:\n
                \n
              • Clear<\/b> to reset the signature.<\/li>\n
              • Save<\/b> to save the signature image.<\/li>\n<\/ul>\n<\/li>\n
              • Connect your IBOutlet and IBAction in ViewController.swift.<\/li>\n<\/ol>\n

                import UIKit<\/p>\n

                 <\/p>\n

                class ViewController: UIViewController {<\/p>\n

                 <\/p>\n

                @IBOutlet weak var signatureView: SignatureView!<\/p>\n

                @IBOutlet weak var imageView: UIImageView!<\/p>\n

                 <\/p>\n

                @IBAction func clearSignature(_ sender: UIButton) {<\/p>\n

                signatureView.clear()<\/p>\n

                imageView.image = nil<\/p>\n

                }<\/p>\n

                 <\/p>\n

                @IBAction func saveSignature(_ sender: UIButton) {<\/p>\n

                let signature = signatureView.getSignatureImage()<\/p>\n

                imageView.image = signature<\/p>\n

                UIImageWriteToSavedPhotosAlbum(signature, nil, nil, nil)<\/p>\n

                }<\/p>\n

                }<\/p>\n

                 <\/p>\n

                Saving Signatures to PDF (Optional)<\/b><\/h3>\n

                You can also save the signature as a PDF for contracts or forms:<\/p>\n

                func saveSignatureAsPDF(signature: UIImage) {<\/p>\n

                let pdfData = NSMutableData()<\/p>\n

                UIGraphicsBeginPDFContextToData(pdfData, CGRect(origin: .zero, size: signature.size), nil)<\/p>\n

                UIGraphicsBeginPDFPage()<\/p>\n

                signature.draw(in: CGRect(origin: .zero, size: signature.size))<\/p>\n

                UIGraphicsEndPDFContext()<\/p>\n

                 <\/p>\n

                let documentsPath = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first!<\/p>\n

                let pdfPath = documentsPath.appendingPathComponent(“signature.pdf”)<\/p>\n

                pdfData.write(to: pdfPath, atomically: true)<\/p>\n

                print(“Saved PDF to: \\(pdfPath)”)<\/p>\n

                }<\/p>\n

                 <\/p>\n

                Testing and Debugging<\/b><\/h3>\n
                  \n
                • Run the app on simulator<\/b> or a real device<\/b>.<\/li>\n
                • Draw your signature and verify it appears in UIImageView.<\/li>\n
                • Test clear<\/b> and save<\/b> functionality.<\/li>\n
                • For PDFs, check the Documents folder in the simulator or use Files app on a real device.<\/li>\n<\/ul>\n

                  Developer Tips<\/b><\/h3>\n
                    \n
                  • Adjust strokeColor and lineWidth for signature style.<\/li>\n
                  • Consider adding undo functionality<\/b> by keeping a history stack of lines.<\/li>\n
                  • For production apps, secure signature storage and encryption may be required.<\/li>\n
                  • Optimize performance for large signature images by limiting the number of stored points.<\/li>\n<\/ul>\n

                    FAQs<\/b><\/h3>\n

                    Q1: Can I capture signatures in SwiftUI?<\/b>
                    \n<\/b>Yes! You can wrap SignatureView in UIViewRepresentable to use it in SwiftUI apps.<\/p>\n

                    Q2: How do I add multiple pages for signatures in PDF?<\/b>
                    \n<\/b>Use UIGraphicsBeginPDFPage() for each page and draw signatures separately.<\/p>\n

                    Q3: How to export signatures to cloud storage?<\/b>
                    \n<\/b>Convert the signature image to Data using pngData() or jpegData() and upload to Firebase, AWS S3, or your preferred backend.<\/p>\n

                    Q4: Can I customize the pen color and thickness?<\/b>
                    \n<\/b>Yes! Modify strokeColor and lineWidth in SignatureView. You can add a UI picker for dynamic selection.<\/p>\n

                    Q5: How to optimize for large screen devices like iPad?<\/b>
                    \n<\/b>Scale the drawing points relative to the bounds.size to maintain proportionality on all devices.<\/p>\n

                    Conclusion<\/b><\/h3>\n

                    Capturing digital signatures in iOS is simple and highly practical for modern apps. By using a custom UIView and Swift 5, you can build a robust, reusable, and customizable signature feature<\/b>. This tutorial equips you with the core functionality, plus optional PDF export for real-world applications.<\/p>\n

                    CTA:<\/b> Ready to add digital signature functionality to your app? Try this Swift 5 implementation and integrate it with your forms or contracts today!<\/p>\n","protected":false},"excerpt":{"rendered":"

                    Digital signatures are essential for mobile apps that handle contracts, forms, or approvals. Whether you\u2019re building a banking app, a document management system, or a delivery app, enabling users to sign directly on their device enhances usability and compliance. In<\/p>\n","protected":false},"author":1,"featured_media":391,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"spay_email":""},"categories":[1],"tags":[],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/www.inwizards.com\/blog\/wp-content\/uploads\/2017\/04\/pizap.com14913723754261.jpg?fit=1023%2C433&ssl=1","_links":{"self":[{"href":"https:\/\/www.inwizards.com\/blog\/wp-json\/wp\/v2\/posts\/390"}],"collection":[{"href":"https:\/\/www.inwizards.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.inwizards.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.inwizards.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.inwizards.com\/blog\/wp-json\/wp\/v2\/comments?post=390"}],"version-history":[{"count":5,"href":"https:\/\/www.inwizards.com\/blog\/wp-json\/wp\/v2\/posts\/390\/revisions"}],"predecessor-version":[{"id":3492,"href":"https:\/\/www.inwizards.com\/blog\/wp-json\/wp\/v2\/posts\/390\/revisions\/3492"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.inwizards.com\/blog\/wp-json\/wp\/v2\/media\/391"}],"wp:attachment":[{"href":"https:\/\/www.inwizards.com\/blog\/wp-json\/wp\/v2\/media?parent=390"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.inwizards.com\/blog\/wp-json\/wp\/v2\/categories?post=390"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.inwizards.com\/blog\/wp-json\/wp\/v2\/tags?post=390"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}