Bugs Found in Lumo by Proton for Android
Lumo by Proton is a highly innovative app that provides a reliable AI assistant to boost productivity and manage everyday tasks. As a Proton product, the app guarantees confidentiality and data protection.
Using Lumo lets you have private chats with an AI assistant and keeps your data secure. The app offers a wide range of features and a user-friendly design that boosts user experience.
The QAwerk team conducted a detailed bug crawl of the Lumo app. The core functionality is robust, and the application is promising. However, we discovered several issues, including major bugs that hinder critical user flows. See our report below for details on these issues and how to remedy them.
‘400. That’s an error’ is displayed after signing in with Google during ‘Easy Switch’ import flow
Severity:
Critical
Precondition:
Log in to the account.
Steps to Reproduce:
- Open the Lumo chat screen.
- Tap the burger menu in the top left corner.
- Tap the ‘Profile’ section at the bottom of the side menu.
- Tap the ‘Settings’ button.
- Tap the burger menu again on the ‘Settings’ page.
- Select the ‘Import via Easy Switch’ option.
- Tap the ‘Google’ button.
- Enter valid Google login credentials (email and password).
Environment:
Xiaomi Mi 10
Android 13 TKQ1.221114.001
Xiaomi HyperOS 1.0.1.0
Actual Result:
After entering the Google login credentials, the import flow fails, and a Google error page is shown with the message: ‘400. That’s an error. The server cannot process the request because it is malformed. It should not be retried.’
Expected Result:
After a successful Google sign-in, the user should be redirected back to the import flow and allowed to continue importing mail/data via Easy Switch.
‘Stop Response’ button does not interrupt response generation
Severity:
Critical
Precondition:
Log in to the account.
Steps to Reproduce:
- Open the Lumo chat screen.
- Enter a prompt in the message input field.
- Send the message and wait until the AI starts generating a response.
- Tap the ‘Stop Response’ button while the response is still being generated.
Environment:
Xiaomi Mi 10
Android 13 TKQ1.221114.001
Xiaomi HyperOS 1.0.1.0
Actual Result:
The ‘Stop response’ fails to work. The response generation continues and completes instead of stopping.
Expected Result:
Tapping the ‘Stop Response’ button should stop response generation immediately.
‘Recovery Kit’ PDF download does not start after registration
Severity:
Critical
Steps to Reproduce:
- Complete the account registration process.
- Navigate to the ‘Secure your account’ screen and locate the ‘Recovery Kit’ section.
- Tap the ‘Download PDF’ button.
Environment:
Xiaomi Mi 10
Android 13 TKQ1.221114.001
Xiaomi HyperOS 1.0.1.0
Actual Result:
The download does not start after tapping the ‘Download PDF’ button. The ‘Recovery Kit’ PDF is not downloaded to the device.
Expected Result:
Tapping the ‘Download PDF’ button should trigger the ‘Recovery Kit’ PDF download.
JPEG image upload fails with ‘Unsupported file type’ error message displayed when selecting photo from device
Severity:
Major
Precondition:
Log in to the account.
Steps to Reproduce:
- Open the Lumo chat screen.
- Tap the ‘Attach File’ button in the chat input area.
- Tap the option to ‘Upload from device’.
- Select a photo from the device gallery.
Environment:
Xiaomi Mi 10
Android 13 TKQ1.221114.001
Xiaomi HyperOS 1.0.1.0
Actual Result:
The selected image is not uploaded. The file preview shows an error message, ‘Unsupported file type’, and a red toast appears stating that the selected JPEG file cannot be processed because it is an unsupported file type.
Expected Result:
The selected image should be uploaded successfully and attached to the chat message input without any error.
Failure to launch PayPal payment flow after selecting ‘PayPal’ button under payment methods
Severity:
Major
Precondition:
Log in to the account.
Steps to Reproduce:
- Open the Lumo chat screen.
- Tap the burger menu in the top left corner.
- Tap the ‘Profile’ section at the bottom of the side menu.
- Tap the ‘Settings’ button.
- Select the ‘Add PayPal’ option on the dashboard screen, in the ‘Payment methods’ section.
- Tap the ‘PayPal’ button in the ‘Add PayPal payment method’ modal.
Environment:
Xiaomi Mi 10
Android 13 TKQ1.221114.001
Xiaomi HyperOS 1.0.1.0
Actual Result:
The PayPal payment flow does not launch when tapping the ‘PayPal’ button. The user is not redirected to PayPal to continue adding the payment method.
Expected Result:
After tapping the ‘PayPal’ button, the app should open the PayPal authorization/payment flow and redirect the user to PayPal to add it as a payment method.
Lumo logo leads to previous page rather than main chat screen when tapped
Severity:
Major
Precondition:
Log in to the account.
Steps to Reproduce:
- Open the Lumo chat screen.
- Tap the burger menu in the top left corner.
- Tap the ‘Profile’ section at the bottom of the side menu.
- Tap the ‘Settings’ button.
- Navigate through different tabs/pages within the settings area.
- Tap the Lumo logo / ‘Back to Lumo’ option at the top of the screen.
Environment:
Xiaomi Mi 10
Android 13 TKQ1.221114.001
Xiaomi HyperOS 1.0.1.0
Actual Result:
Instead of returning the user to the main chat screen, tapping the logo performs a single-step back navigation and opens the previous settings page/tab.
Expected Result:
Tapping the Lumo logo / ‘Back to Lumo’ option should return the user directly to the main Lumo chat screen.
Uploaded PDF file is difficult to remove because ‘Delete’ icon is not persistently visible
Severity:
Major
Precondition:
Log in to the account.
Steps to Reproduce:
- Open the Lumo chat screen.
- Tap the ‘Attach File’ button in the chat input area.
- Select the ‘Upload from device’ option.
- Select a PDF file from the device gallery.
- Try to remove the uploaded file before sending the message.
Environment:
Xiaomi Mi 10
Android 13 TKQ1.221114.001
Xiaomi HyperOS 1.0.1.0
Actual Result:
The ‘Delete’ (‘X’) icon is not fixed and persistently visible on the uploaded file tile. When the user taps the file, its preview opens, and the ‘Delete’ icon only flashes briefly. As a result, the file can only be removed with an awkward workaround, such as tapping very quickly in the area where the icon appears or using an unusual press/swipe action.
Expected Result:
The ‘Delete’ (‘X’) icon should be clearly visible and fixed on the uploaded file immediately after upload, allowing the user to remove the attachment easily with a normal tap.
System ‘Back’ button closes setting flow instead of dismissing only pop-up
Severity:
Minor
Precondition:
Log in to the account.
Steps to Reproduce:
- Open the Lumo chat screen.
- Tap the burger menu in the top left corner.
- Tap the ‘Profile’ section at the bottom of the side menu.
- Tap the ‘Settings’ button.
- Select the ‘Add PayPal’ option on the Dashboard screen, in the ‘Payment methods’ section.
- When the ‘Add PayPal payment method’ pop-up is displayed, tap the system ‘Back’ button.
Environment:
Xiaomi Mi 10
Android 13 TKQ1.221114.001
Xiaomi HyperOS 1.0.1.0
Actual Result:
The system ‘Back’ button navigates the user away from the current settings flow instead of simply dismissing the pop-up.
Expected Result:
The system ‘Back’ button should close only the pop-up and keep the user on the same settings page.
‘Like/Dislike’ selection is not preserved when switching between response variants
Severity:
Minor
Precondition:
Log in to the account.
Steps to Reproduce:
- Open the Lumo chat screen.
- Enter a prompt and send it.
- Wait for the AI response to appear.
- Edit the first prompt.
- Wait for a new response.
- Tap the ‘Like’ button for the selected response.
- Switch to another response variant.
- Switch back to the original response variant.
Environment:
Xiaomi Mi 10
Android 13 TKQ1.221114.001
Xiaomi HyperOS 1.0.1.0
Actual Result:
The previously selected ‘Like/Dislike’ feedback is not preserved after switching between response variants.
Expected Result:
The selected ‘Like/Dislike’ feedback should remain for the specific response variant even after switching to other variants and back.
Prompt ‘Collapse/Expand’ button does not work on request message
Severity:
Minor
Precondition:
Log in to the account.
Steps to Reproduce:
- Open the Lumo chat screen.
- Send a prompt that appears as an expanded request/message block in the chat.
- Locate the ‘Collapse/Expand’ button on the prompt block.
- Tap the ‘Collapse/Expand’ button.
Environment:
Xiaomi Mi 10
Android 13 TKQ1.221114.001
Xiaomi HyperOS 1.0.1.0
Actual Result:
Nothing happens after tapping the ‘Collapse/Expand’ button. The prompt/request block remains expanded rather than collapsed.
Expected Result:
Tapping the ‘Collapse/Expand’ button should collapse the prompt/request block. Tapping it again should expand it back.
Chat fails to auto-scroll to bottom during response generation
Severity:
Trivial
Precondition:
Log in to the account.
Steps to Reproduce:
- Open the Lumo chat screen.
- Enter a prompt and send it.
- Wait until the AI starts generating a long response.
- Observe the chat position during generation.
- Optionally, tap the ‘Down Arrow’ button to jump to the bottom of the message.
- Continue observing the chat while the response is still being generated.
Environment:
Xiaomi Mi 10
Android 13 TKQ1.221114.001
Xiaomi HyperOS 1.0.1.0
Actual Result:
The chat does not automatically follow the newly generated text. Even after tapping the ‘Down Arrow’ button and moving to the bottom, the screen stays fixed in place while more text is generated below.
Expected Result:
While the response is being generated, the chat should automatically scroll and keep the latest generated text visible, especially after the user taps the ‘Down Arrow’ button to move to the bottom.
‘Account’ pop-up briefly shows incorrect button label before updating to final text
Severity:
Trivial
Precondition:
Log in to the account.
Steps to Reproduce:
- Open the Lumo chat screen.
- Tap the burger menu in the top left corner.
- Tap the ‘Profile’ section at the bottom of the side menu to open the ‘Account’ pop-up.
- Observe the second button in the pop-up.
Environment:
Xiaomi Mi 10
Android 13 TKQ1.221114.001
Xiaomi HyperOS 1.0.1.0
Actual Result:
The label of the second button momentarily displays the text ‘Switch or add account’ before changing to ‘Add another account’.
Expected Result:
The button label should immediately display the correct text, ‘Add another account’, without any intermediate or incorrect text showing first.
I tested the Lumo Android app with a focus on the main user journeys, including chat interactions, settings, account flows, payments, import, file attachments, and response controls. During testing, I found several functional and UX issues, including broken PayPal and Google import flows. Based on the results, I recommend validating the product against both functional and non-functional requirements using a mix of smoke, regression, exploratory, negative, compatibility, usability, and basic performance/stability testing.
