How to do digital signature On a mobile phone, it involves using an app or platform to send the document, designate signatories, and finalize the digital signature. The process works on Android or iOS and guarantees the legal validity of the document, according to authentication and integrity requirements.
How to create a digital signature on your mobile phone has become essential for companies and users who need to securely validate documents online. The process involves using apps, sending PDFs, defining signatories, and digitally signing in encrypted format.
After all, today, the digital signature is established as an essential technology for the operation of all types of business, gradually replacing the traditional paper signature.
However, many people still have doubts about how to use this feature, with "how to create a digital signature on a mobile phone" being one of the most frequent questions. Considering that, in Brazil, more than half of the people with internet access use it via mobile phone, the importance of clarifying this point becomes evident.
Thinking about it, we prepared this article on the subject. Following the step-by-step we prepared, you won't have any difficulties closing your digital contracts on your cell phone. Let's go?
Summary
- Technical definition of digital signature and legal validity.
- Steps to create a digital signature on your mobile phone using Android and iOS applications.
- Detailed step-by-step guide to the workflow within ZapSign.
- Methods for sending the subscription link and authentication options.
- Signatory process
- Advantages: mobility, speed, and greater reach.
Quick facts
- Electronic signatures without an ICP-Brasil certificate can also have probative value if they meet the requirements of authenticity and integrity. as recognized by the Superior Court of Justice in 2025.
- Approximately 30% of documents are signed electronically. They are sent or completed directly on mobile devices, reinforcing the use of cell phones in digital processes.
- The global volume of digital signatures made on smartphones. surpassed 51 billion, with projections to reach over 75 billion in the coming years.
What is a digital signature and why is it legally valid?
A digital signature is a type of electronic signature whose concept is linked to the use of any electronic or digital mechanism to validate the authorship of an act.
In other words, it is a resource that proves the identity of its signatories in a secure way, using cryptography, a virtual key and digital certificate
These digital certificates are issued by a Brazilian certification authority, following the standards established by the Brazilian Public Key Infrastructure (ICP-Brazil). According to their characteristics, certificates are divided into different categories, such as A1 and A3. Some examples of digital certificates are the e-CNPJ and the OAB token used by lawyers.
The digital signature, therefore, assumes the same legal validity of a handwritten signature on paper documents – as defined by article 10, paragraph 2, of the Provisional Measure No. 2.200-2/2001 and by Provisional Measure No. 983 of 2020.
💡 Tip! Need a free digital signature? Click here and create yours now!
How to create a digital signature on your mobile phone: essential steps
Carrying out a digital signature on cell phones, whether on Android or iOS devices, can be carried out in a practical and efficient way.
Next, we will show you step by step how to use a specific application to digitally sign documents. Through an intuitive and accessible process, we will highlight the ease of the procedure, exemplified by the use of ZapSign's digital signature.
Step 1: Register on the platform
First, you need to register on the ZapSign platform to be able to digitally sign your contract. It has three special plans for companies: the professional plan, the team plan and the complete plan:
Professional Plan
Indicated for small companies, with a low flow of monthly documents, this plan allows you to sign up to 20 contracts per month. The professional plan also allows the inclusion of up to 6 users, with a price starting at R$29,90 per month;
Team Plan
This intermediate plan includes the signing of up to 75 documents per month. The team plan also allows the inclusion of up to 8 users, starting at R$79,90 per month;
Complete Plan
Aimed at companies with a large flow of documents, the complete plan guarantees an unlimited amount of monthly subscriptions, in addition to the inclusion of up to 11 users, costing from R$99 per month.
It is worth remembering that if you are still not sure which of the three plans represents the most appropriate option for your business, or if you simply want to try the tool before making the purchase, there is also the essential plan.
With the essential plan, you can send up to 5 documents per month Delivery to Italy takes one or two business days. Considering that this might be your first time using ZapSign, we'll use the essential plan as the basis for this tutorial.
When accessing the ZapSign home page on your mobile phone, tap on “Try it for free”.
Afterwards, the registration screen will appear. Here, you will have to enter your email, as well as a password of at least 6 characters, which will be used for your login when registration is complete. After entering this data, tap on “Create Account”.
In just two steps, your ZapSign registration is successfully completed and you are ready for the next step.
Step 2: Upload the document to the platform
O file to be signed must be in .PDF format – therefore, you need to have the document saved in this format. If the file is on Google Drive, just go to “File / Download / PDF Document”. If it is a .doc file, there are applications like this who can perform the conversion for you.
Then, as the print above says, click on the “+” button to upload the document to be signed on the platform. Upon doing so, you will be presented with the following screen.
Now, tap on “Select Document”, and you will be taken to choose the PDF file you have on your mobile.
Step 3: Determine the signatories
After the file upload is completed, you must point out the respective names of the signatories of the agreement.
It is worth mentioning that there is an option for “Advanced Authentication” aimed at inserting more data of the people who sign, such as: email, phone number, function, selfie and photo of an identification document. To proceed, tap “Continue”.
Next, you can position in which part of the document the signature should be made. In physical contracts, it is common for the signature field to be located at the end and it is inserted in a line present above the signatory's name. As many people are still used to this format, we adapted it to ZapSign to better identify the traditional audience.
If you don't see this function as necessary, just tap on “Continue without positioning”. But, if you have done the placement, tap on “Save and continue”.
Step 4: Send the subscription link
On the next screen, you will be asked to collect signatures. There are three different ways to do this.
The first way is to copy the document link by tapping the blue icon. With the link in your clipboard, it can be sent via any messaging channel you prefer.
By the way, if you're talking to signatories over WhatsApp, there is a special icon for you to send the document directly from the application. This is the second shipping method.
Finally, there is the third way. To activate it, you can tap on the button that says “I want ZapSign to send signature links to signers” which will bring up the following screen.
If you want, here you can put the email and a personalized message for your signatory. To finish, tap “Send and finish” and that’s it – the document has been sent for signature.
Step 5 – the signature of the signer
After you send the document, the person signing must tap on the received link in order to view the document and the signature button.
After the ring, the person will be invited to enter their full name, email and contact phone number. After entering this information, you must tap on “Continue”.
The next screen presents a very interesting feature of ZapSign: the person can sign the document with his finger, just as he does when signing physical files with a pen. The signature will probably not look identical to the identity document, but that doesn't matter. After signing, just tap on “Checkout”.
Ready! After following these steps, the digital signature is successfully completed. The screen below is displayed and a confirmation email is also sent by the platform to both parties.
| Stage / Resource | Technical function | Practical application on mobile phones |
|---|---|---|
| Platform registration | Initial user identification | Create an account and log in to the app. |
| Upload the document (PDF) | Digital format conversion and compatibility | Selecting a file from local storage |
| Definition of signatories | Associating identity with documents. | Inserting names and using advanced authentication. |
| Sending the subscription link | Communication between the parties | Link sent via message, WhatsApp, or automated delivery. |
| Signature by the signatory | Digital signature registration | Fingerprint signature and data validation |
⚠️ Also check out these related articles ????
➡️ Learn how to sign with a digital certificate
➡️ Understand what a digital signature verifier is for
➡️ What is a digital contract and how to adopt one for your company
Advantages of digital signatures via mobile phone
The digital signature by cell phone offers a series of practical advantages, but we can highlight three as being the main ones: mobility, speed and simplicity.
Student Exchange
Digitally signing via cell phone allows contracts to be signed from anywhere. Even if you and your client are very busy with your routine tasks and it is difficult to reconcile your respective schedules to meet and carry out the firm, this way this will not be a problem.
Apart from that, even when both parties have already adhered to the digital signature, the cell phone signature is very useful so that a computer is not necessary to close the digital contract. Even if one of the parties is far from the office, just pick up the cell phone and quickly sign, as shown above.
Speed
Agility is another great advantage of digital signatures on your cell phone. This is because the loading speed of the sites is usually faster on mobile devices than on desktop devices: according to Google, the average loading time of a website via cell phone takes just 3 seconds, which definitely makes the process quicker.
greater reach
Second data released by the Internet Steering Committee in Brazil (CGI.br), 74% of the Brazilian population has access to the Internet. Among these people, 58% have cell phones as their only means of accessing the network. Based on this information, most online stores were forced to optimize the mobile versions of their websites in order to serve such a significant portion of the public.
Now that you know how to make a digital signature on your cell phone and what are the advantages of this practice, how about getting to know ZapSign's digital signature solution? Just click here to check it out!
Frequently Asked Questions (FAQ)
How do you create a digital signature using a mobile phone?
Digital signatures via mobile phone are made through a platform or application. The user sends the document in PDF format, defines the signatories, positions the signature, and finalizes the process directly on the device.
How do I digitally sign a PDF document using my mobile phone?
Simply select the PDF file in the application, upload it, define the signatories, and apply the digital signature. The system records the authentication and integrity of the document.
Is it possible to get a free digital signature on your cell phone?
Yes. Some platforms offer free plans that allow you to send a limited number of documents per month. The process includes registration, uploading, and completing the digital signature.
How does digital signature work via WhatsApp?
The signature link can be sent via WhatsApp. The signatory accesses the document, enters basic information, signs with their finger, and completes the transaction directly in the app.
Is a digital signature on a mobile phone legally valid?
Yes. As long as they meet the requirements of authenticity and integrity, digital signatures have legal validity equivalent to a handwritten signature, according to current regulations.
Getúlio Santos is the CEO of ZapSign, a lawyer, technology enthusiast, and entrepreneur.
