よくあるご質問（FAQ） Frequently Asked Questions

Yes. The first 7 days are a free trial with full access to all features and unlimited sending. After the trial, you can continue on the free plan (3 memos per day).

Monthly and annual plans are available. Annual plans offer a discount compared to monthly pricing. Check the in-app subscription screen for current pricing in your region.

In Settings, open the Premium section and tap "View Plans & Subscribe". This opens the Paywall screen, which shows:

• Monthly and yearly plan names, duration, and localized price
• Auto-renewal and cancellation details
• Links to the Terms of Use and Privacy Policy
• The "Restore Purchases" button

You'll also see an upgrade prompt when you hit the free plan's daily send limit.

The trial starts when you subscribe. The first 7 days after purchase are free — you won't be charged during that window, and you can cancel anytime within it without being billed. All features are unlimited during the trial.

If you prefer not to subscribe, you can keep using the free plan (3 sends per day) indefinitely.

Through Apple's subscription management:

1. Open the Settings app on your iPhone
2. Tap your name at the top
3. Tap "Subscriptions"
4. Select "Simple Memo Premium"
5. Tap "Cancel Subscription"

You'll retain Premium access until the end of the current billing period. Cancelling during the 7-day trial means no charge at all.

Yes. Open the Premium section in Settings, tap "View Plans & Subscribe", then tap "Restore Purchases" at the bottom of the Paywall screen. As long as you're signed in with the same Apple ID, your subscription will be restored.

The App Store product information hasn't loaded yet. Try this:

1. Check your network connection (Wi-Fi or cellular)
2. Tap the "Tap to load" button to retry fetching product info
3. Once the products load successfully, you can proceed straight into the purchase flow
4. If it keeps failing, verify you're signed in under iOS Settings > Apple ID > Media & Purchases

Memos are sent as emails to your verified recipient address. The sender appears as Simple Memo <[email protected]>.

The subject is generated automatically:

• If a subject template is set: Template + first line of memo (e.g., "Simple Memo Grocery list for today")
• If the subject template is empty: The first line of your memo becomes the subject
• If the memo starts with blank lines: The first line containing text is used
• Subject lines are truncated at 60 characters

Yes. In Settings, enter text in the "Signature" field. It will be appended to every memo with a -- separator line.

Yes. Simple Memo clears the screen instantly after you tap send (target: under 150ms). Your memo is processed in the background. Even if the network request fails, the memo is safely stored in the encrypted Outbox and will be retried automatically. Your memo is never lost.

Yes, but a 1.5-second cooldown is enforced between sends to prevent accidental double-taps. Tapping during cooldown shows a brief "Please wait" message.

Yes. When you send a memo offline, it's stored in the Outbox — encrypted with AES-GCM on your device. When connectivity is restored, all pending memos are sent automatically.

An orange banner appears at the top of the screen reading "Offline -- will send when connected." It disappears automatically when the network is restored.

Yes. Outbox messages are encrypted and written to persistent storage. They survive app termination, device restarts, and iOS memory management. On next launch (or via background tasks), delivery is reattempted automatically.

Yes. Tap the clock icon in the top-left corner of the main screen to open the History view, which shows all sent, pending, and failed memos.

For each memo:

• Text preview (up to 10 lines)
• Date and time
• Status: Sent / Pending / Failed

Yes. Tap a memo in History and select "Resend." The same message ID is reused to prevent duplicate delivery on the server side (idempotency guarantee).

Yes. Tap a memo and select "Share" to open the standard iOS share sheet (copy, AirDrop, Messages, etc.).

No. Your memo content is never stored on Simple Memo's servers. Memos pass through the Relay API for email delivery, but no data is retained after transmission. All on-device data (Outbox and History) is stored only on your device, encrypted with AES-GCM.

Simple Memo encrypts all locally stored memo data (Outbox and History) with AES-GCM (256-bit):

• Encryption keys are stored in the Keychain, protected by the device's Secure Enclave
• Files are protected with Apple's Data Protection (completeUntilFirstUserAuthentication)
• Encryption keys never leave your device

Yes. All communication between the app and the Relay API (Cloudflare Workers) uses HTTPS (TLS). Additional protections:

• HMAC signatures: every request is HMAC-SHA256 signed, detecting tampering.
• Static API key auth: a dedicated API key is required to reach the relay.
• Ephemeral URLSession: the client uses an ephemeral URLSession, so no network cache, cookies, or URL cache is ever stored on disk.
• Idempotency-Key: each send carries a unique message ID, so the server can deduplicate retries automatically.

No. The Relay API simply forwards your message body to Resend for delivery and does not retain the message afterward. What is briefly stored in Cloudflare KV is hashed/anonymized:

• Email addresses are stored as a 128-bit hash (for rate limiting)
• Verification codes use constant-time comparison and auto-expire after 10 minutes
• Device tokens are hashed and used only for rate-limit counters

On-device, Outbox and history data are AES-GCM encrypted, with keys held in the Keychain.

No. When the app moves to the background, a privacy overlay (showing only the app icon and title) is immediately placed over the screen. Your memo content is never visible in the multitasking view.

No. Email addresses, memo text, verification codes, tokens, and URLs are never written to any log — including DEBUG builds. Error logs only record the error type name, never the detailed message.

Yes. Like the Outbox, History data is stored on-device with AES-GCM (256-bit) encryption. The encryption key is stored in the Keychain and protected by Apple's Data Protection (completeUntilFirstUserAuthentication).

Uninstalling the app removes all data from your device, including Outbox messages, History, settings, and encryption keys stored in the Keychain.

To prevent unauthorized sending to someone else's email address. Verification confirms that you own the email address you're sending memos to. This is a critical safety measure.

Simple Memo is a memo app focused on one thing: launch, write, send. Your memo is sent as an email to a pre-configured address with a single tap. There are no folders, tags, sync settings, or complex features. It's designed to capture your thoughts instantly and deliver them to your inbox -- nothing more, nothing less.

• Sending yourself a quick shopping list
• Jotting down ideas while commuting
• Recording key takeaways from a meeting
• Emailing yourself task reminders
• Saving URLs, phone numbers, or addresses for later
• Quick brain-dumps before you forget

When you first launch the app, you'll be prompted to set up a recipient email address:

1. Tap "Go to Settings" in the setup dialog (or open Settings manually)
2. Enter the email address where you want to receive your memos
3. Tap "Verify"
4. Enter the 6-digit verification code sent to that email
5. Done -- you're ready to send memos

Yes. Go to Settings, tap "To", enter a new email address, and complete the verification process again. All future memos will be sent to the newly verified address.

Go to Settings → Email Settings. At the bottom of the section, tap "Clear Recipient" (shown in red). Confirm in the dialog to wipe:

• The saved recipient email address
• Verified-email status (stored in Keychain)
• Any legacy verification data from older versions

After clearing, the "To" field is empty, the verification checkmark disappears, and you'll need to set up again before sending. Useful if you want to switch to a different account or re-run verification.

Yes. Open Settings and tap "How It Works". You'll see a 3-step visual guide:

1. Email setup — register and verify your recipient email
2. Write a memo — keyboard appears on launch; start typing instantly
3. Send — one tap delivers the memo to your inbox

Translated into all 10 supported languages.

All of them. Gmail, Outlook, Yahoo Mail, iCloud Mail, corporate email, custom domains -- any address that can receive email will work.

A text prefix added to the email subject of every memo you send. For example, if you set it to "Simple Memo" and your memo's first line is "Grocery list," the subject becomes "Simple Memo Grocery list." Leave it empty to use only the first line of your memo as the subject.

Yes. Go to Settings, then "Sound & Haptics" to toggle the send sound on or off. Haptic feedback remains active regardless of this setting. Note: the sound is automatically muted when your device is in Silent Mode.

Yes. Simple Memo follows your iOS system appearance setting automatically. There is no separate in-app theme toggle.

No. Simple Memo is an independent app inspired by Captio. It has no affiliation with the original Captio developer. Our goal is to recreate and build upon the "launch, type, send, clear" experience that made Captio beloved.

Simple Memo preserves Captio's core experience while adding modern improvements:

• Outbox with auto-retry: Memos are never lost, even offline
• AES-GCM encryption: All on-device data is encrypted
• Privacy overlay: Memos are hidden in the App Switcher
• 10 languages: Including Arabic with full RTL support
• Email verification: 6-digit code verification prevents unauthorized sending
• Send animation: 3D page-flip animation with haptic feedback

No. Simple Memo does not support data import from the original Captio app, as they are independent applications with no data compatibility.

No. Simple Memo is designed exclusively for fast text memo delivery and does not support image attachments. For saving photos, use Apple's built-in Photos or Notes app. Simple Memo is a dedicated tool for capturing thoughts as text, instantly.

• iPhone (iOS 16.0 or later)
• iPad (iPadOS 16.0 or later)

The target for Time-to-Text (from launch to keyboard ready) is under 500 milliseconds. In real-world testing, most devices achieve 200-300ms. This is made possible by using UIKit with direct initialization -- no Storyboards, no SwiftUI overhead.

No. Simple Memo is built entirely with Swift and Apple-native frameworks (CryptoKit, Network.framework, BackgroundTasks, StoreKit 2). Zero external dependencies means a smaller app size and minimized security risk.

Simple Memo supports 10 languages: Japanese, English, Spanish, French, German, Portuguese, Russian, Chinese (Simplified), Chinese (Traditional), and Arabic.

Go to Settings, then "Language." Changes take effect immediately across the entire app (the interface reloads automatically).

Yes. When Arabic is selected, text direction, UI layout, and navigation bar button placement all switch to RTL automatically.

No. Background network operations are minimal. Outbox retry uses iOS's BGTaskScheduler, which intelligently schedules retries during optimal conditions (e.g., while charging, on Wi-Fi). The app does not run continuously in the background.

Please check the following:

• Verify there are no typos in your email address
• Check your spam/junk folder
• The sender is Simple Memo <[email protected]>
• Verification codes expire after 10 minutes -- request a new one if expired
• You have a maximum of 5 attempts per code -- request a new code if exceeded

You need to set up and verify a recipient email in Settings before you can send memos.

Your recipient email verification is incomplete. Go to Settings, tap "Verify" next to your email address, and complete the 6-digit code verification flow. This is also required after changing your email address.

You've sent too many memos in a short period. The following limits apply:

Wait a moment and try again. Memos stored in the Outbox will be retried automatically once the limit resets. Typical usage (a handful of sends per day) won't hit these limits.

The Relay API server is experiencing a temporary issue. This usually resolves within minutes. Your memo is safely stored in the Outbox and will be resent automatically once the server recovers. If the issue persists, please contact support.

Check the following:

1. Your recipient email is correctly verified
2. Your network connection is stable
3. Check your spam/junk folder
4. Ensure simplememofast.com isn't blocked by your email provider's filters

Please check:

• Your network connection is stable
• Your recipient email is still verified
• Each message retries up to 5 times -- messages that exceed this limit are marked as failed
• You can manually retry from the History screen

No. When you tap send, your memo is saved to the encrypted Outbox before any network request is made. If the app crashes, memos in the Outbox remain intact. They'll be retried automatically when you relaunch the app.

This can happen if the server response is lost (e.g., network timeout, app backgrounding) while the send has already completed on the server. v1.5 addresses this in several ways:

• Automatic retry after 5 seconds: if the client treats a send as timed out, it retries once in the background.
• Retry on foreground: any pending messages are retried the moment the app returns to the foreground.
• Duplicate prevention: every send path uses the same Idempotency-Key, so even if the server already accepted the message, you won't receive the email twice.
• Self-healing history: once a retry succeeds, the history entry flips to "Sent" automatically.

Net result: "Pending" may show briefly, but only one actual email is delivered.

Yes. Starting with v1.5, each send is tracked by a unique history entry ID (not by message text). Sending "OK" three times in a row now produces three distinct history entries, each correctly marked "Sent" (earlier versions could misattribute status when duplicate bodies were pending).

You can reach us through:

• Email: support@simplememofast.com
• App Store review: Via the in-app rating prompt or the App Store review section

• Terms of Use: https://simplememofast.com/terms
• Privacy Policy: https://simplememofast.com/privacy

No. Simple Memo does not support data import from the original Captio app, as they are independent applications with no data compatibility.

You can reach us through:

• Email: support@simplememofast.com
• App Store review: Via the in-app rating prompt or the App Store review section

• Terms of Use: https://simplememofast.com/terms
• Privacy Policy: https://simplememofast.com/privacy

Simple Memo is developed and operated by YURIKA, K.K.