Privacy Policy
This policy explains how Premsan Inc (“Premsan”, “we”, “us”) handles personal data in EasyXiv — this website, the web app, the API, and the EasyXiv apps for iPhone, iPad and Android. Premsan is the controller.
1. What we collect
- Your account. Your name, your email address, and either a password — stored only as a hash — or, when you sign in with Apple or Google, your identifier there and the sign-in tokens the provider gives us. Each session records the IP address and the browser or device it was opened from, and when it expires. We also record the date on which you accepted the Terms, and which version.
- Your background and notes. What you tell EasyXiv you do and know, your readings of papers and your notes on ideas: each one’s title, its text, up to 64 earlier versions of it with who wrote each, the links between them, which ideas you marked as known, and when each was created and changed.
- The papers you open. Each paper’s arXiv id, title, authors, abstract, categories, licence and dates, its text as arXiv publishes it, the figures the assistant looked at, made smaller to the size the model reads, and when you opened it.
- What you follow. The arXiv categories and authors you follow, and the latest day’s feed built from them: how many papers it listed, the ones picked for you, and the sentence saying why each was picked.
- Your conversation with the assistant. The messages you send it, the photos you attach, made smaller to the size the model reads, the paper or idea you had open when you wrote, your time zone so it knows what today is, and its replies.
- Your voice. When you turn on voice mode, what you say is recorded and sent to be written down as text; the text goes to the assistant as your message, and the recording is deleted once it is written down. The assistant’s replies are read aloud by your own device’s voice.
- The plan. When your free use began, how many messages you have sent the assistant since, and the state of your subscription. On the web, payment is taken by Stripe: it receives your email address and your account id, and your card details go to Stripe and never reach us. We keep the subscription’s id, your customer id at Stripe, when the current period ends and whether it renews. In the app, payment is taken by the App Store or Google Play; we receive the transaction’s id, confirm it with Apple or Google, and record it against your account.
- Help. When you write to us from Help, we keep your messages, the pictures you attach, and details that help us answer: whether you wrote from the web or the app, your browser or app version and operating system, your language, the screen you were on, the size of your window or screen, your time zone, and your most recent failed requests. They are kept with your account until you delete it. Our team reads them in our own support tool, where, if you have allowed the assistant, EasyXiv’s model may draft a reply that a team member reviews before sending.
- Usage. The number of requests you made to the assistant in the current hour, kept in your own account’s storage for the hourly limit. Server logs hold request metadata, including your IP address, error reports, and the size and cost of each of the assistant’s runs, for a short time, for security, debugging and our accounting.
- The bot check. Cloudflare Turnstile runs on our sign-in and sign-up pages, and in the app’s sign-in screen, to tell a person from a script.
- Nothing else. There is no advertising, no analytics, no tracking across sites or apps, no advertising identifier, and no data broker.
2. What we do with it
We use personal data to run EasyXiv: to fetch the papers you open and keep your notes, search them and show them to you, pick the day’s papers for you, let the assistant read what you send it and write your notes, sign you in, send you the emails the account needs — a verification link and a password reset — take payment and keep your subscription’s state, keep the service running and prevent abuse, answer you when you write to us, and meet legal obligations. We do not use your notes or your conversations to train models, we do not sell personal data, and we do not share it for advertising.
3. Why we are allowed to
Where the GDPR or a law like it applies, we rely on these bases:
- Performing our contract with you — your account, your notes, the papers you open, what you follow, your conversations, and the subscription.
- Our legitimate interests — keeping EasyXiv running, finding failures, and stopping abuse and automated sign-ups. We limit this to the usage counts, the server logs and the bot check.
- A legal obligation — payment records and anything else the law requires us to keep.
If your notes or messages hold personal data about other people, you decide what you keep and why, and you answer to them for it.
4. Who else processes it
EasyXiv runs on Cloudflare: the servers, the storage that holds your account, your notes, the papers you open, your conversation and your photos, the resizing of photos and figures, the model that reads your messages and papers and writes your notes, the email we send, and the bot check are all Cloudflare services on our own account. Nothing the assistant reads goes to any other AI provider. The model runs on Cloudflare Workers AI, and the assistant sends it nothing until you allow that, on the web or in the app, when it asks before your first message or photo; you can turn it off in Settings (under Account in the phone app), and the assistant then asks again before your next message. What it sends is your messages, the photos you attach, your background, what you follow, the papers, figures and notes it reads to answer you, and, when it picks the day’s papers for you, your background with their titles and the start of their abstracts. Some email may be sent through Resend instead.
Papers come from arXiv. When you open or add a paper, or the assistant searches for papers or opens one, our server asks arXiv for it; arXiv sees the paper’s id or the words searched, in a request from our server, which identifies itself as EasyXiv with our support address and keeps to arXiv’s request limits, and nothing about you or your account. The list of each day’s new papers is fetched once for every account, with nothing of anyone’s in the request.
In voice mode, each recording of what you say goes to Cloudflare Workers AI to be written down as text, and to no other provider; we do not keep the recording.
Stripe takes payment on the web and keeps the card; Apple and Google take payment in the app, and each tells us when a subscription you bought there renews, is cancelled or is refunded. When the app opens, it asks Expo’s update service whether a newer version of our code is available; that request carries the operating system, our project id and a random identifier the app created for itself — no account and no device identifier — and Expo sees the IP address it came from. These providers process data only on our instruction and are each bound to protect it at least as well as this policy does; we give notice here before a new one starts.
Signing in with Apple or Google sends us your identifier and email from that provider. Each acts on its own behalf there, not as our processor, and its handling of your account with it is governed by its own privacy policy; if you hide your email from us with Apple, mail reaches you through Apple’s relay. The App Store and Google Play are the sellers of what you buy inside the app, and their handling of your payment is governed by theirs.
5. Where it is
Your data is processed on Cloudflare’s network, which spans the world, and stored on it under Cloudflare’s own commitments for international transfers. Premsan is in Japan, a country the European Commission recognises as protecting personal data adequately.
6. On the phone
The app keeps on your device a sign-in token, the language and appearance you chose, and the random identifier its update check uses; your notes and papers stay in your account and are fetched when you open them. It asks for the camera only when you choose to photograph a page, a figure or a whiteboard for the assistant; you can turn it off in the operating system’s settings. It reads a photo only when you pick one, to send the assistant or to attach to a Help message, through the system’s photo picker, which needs no permission, and it makes a photo smaller before sending it. It uses the microphone only while voice mode is on, and the operating system asks your permission the first time you turn it on. It asks for no other permission, carries no advertising or analytics library, and purchases go through the store’s own sheet.
7. Cookies
On the web we set the cookies the product cannot work without: the one that keeps you signed in, and the ones Cloudflare Turnstile sets to tell a person from a bot on the sign-in and sign-up pages. This website and the web app keep your theme and language in your browser’s own storage. That is the whole list: no advertising cookies, no cross-site trackers, and no analytics that follows you between sites. Clearing them signs you out.
8. How long we keep it, and deleting it
We keep your account, your notes and the papers you open for as long as the account exists. Deleting a note removes it with its earlier versions; removing a paper deletes its text, its figures and your reading of it; unfollowing removes the category or author; and clearing your conversation with the assistant deletes its messages and the photos you attached to them.
You can delete your account at any time: on the web under Account in Settings, or in the app under Account. We then erase everything we hold for you — your notes, the papers you opened and their figures, what you follow and your feed, your conversation and its photos, Help messages, usage counts and the subscription’s state — and then the account itself, and a subscription bought on the web ends. This cannot be undone, so copy your notes first if you want to keep them.
These records remain after the account is deleted:
- A purchase made in the app. We keep the store’s transaction id, the date and the id of the account it was bought for, so that a store sending the same receipt again cannot credit it to another account, and because the law requires payment records to be kept. The account it names no longer exists.
- Payment providers’ records. Stripe, Apple and Google keep their own records of a payment under their own legal obligations.
- Backups. Cloudflare keeps restorable copies of our databases for up to 30 days so that they can be restored after a failure; they then expire.
- Server logs. They are deleted automatically after a short time.
9. Your rights
You can read, change and delete every note, remove any paper, change what you follow, clear your conversation and delete your account in the web app or the phone app, without asking us. Depending on where you live, you may also have the right to a copy of the rest of what we hold about you, to restrict how we process it, to object to processing we base on legitimate interests, and to move your data elsewhere. Write to support@easyxiv.com and we will answer within one month.
If you live in California or another U.S. state with a similar law, you have the right to know what personal data we hold about you, to delete it, and to correct it; the controls above do that. We do not sell or share personal data as those laws define the words, so there is no opt-out to offer, and exercising a right gets you the same service on the same terms.
If you think we have handled your personal data wrongly, you can complain to a data protection authority — in the EEA or the United Kingdom, the one where you live or work or where the problem happened; in Japan, the Personal Information Protection Commission. You may contact us first, but you do not have to.
10. Security
Every connection is encrypted in transit. Passwords are stored as hashes. Each account’s notes, papers, conversation and photos are kept in their own isolated storage and are deleted with the account, apart from the records listed in section 8. The app keeps its sign-in token in the operating system’s secure store. Credentials never enter our server logs. If you find a security weakness, write to security@easyxiv.com and allow us time to fix it before you disclose it to anyone else.
11. Children
EasyXiv is not for anyone under 16, and we do not knowingly hold a child’s account. If you think a child has an account, tell us and we will delete it.
12. Changes
We may update this policy. When a change matters we will say so in the web app or the phone app, or by email. The date at the top is the version that stands.
13. Contact
Premsan Inc — 530-0001, 12-12, Osaka Ekimae Dai-2 Bldg., 1-2-2 Umeda, Kita-ku, Osaka-shi, Osaka, Japan. support@easyxiv.com.