Nexus: Spaced Repetition Tracker

Learn smarter • Remember longer • Offline-first

Saved on this device

Overview

See what needs review and track progress across subjects.

Upcoming review calendar

See review dates and exams across the months ahead.

▦
Plan your next study sessionsMonth-by-month reviews and exam dates

Review queue

Overdue and due topics appear first, followed by new topics.

Progress by subject

Share of active topics reviewed at least once.

Coming up · next 7 days

Plan ahead before topics become overdue.

0 scheduled

Your momentum

Recent study activity from your saved review history.

Last 7 days

Streams & subjects

Organise your courses and subjects here, alongside your topics.

Topics

Add, edit, filter, and review topics from any subject.

Explore curriculum

Browse ready-made study collections and install only the streams, subjects, or topics you want.

CURRICULUM MARKETPLACE

Build your own study workspace

Starter curricula stay here until you choose to add them. Your personal review schedule and history remain yours.

—starter topics

Review history

Each review stores the rating, date, assigned interval, and optional note.

Account & backups

Manage sign-in, cloud sync, and portable backup files separately from study content.

Account & cloud sync

Private sync across your devices

Connecting…
Signed-in account
Checking account…

You can use Nexus offline. Sign in with the same account to preserve and merge unsynced offline work. Switching accounts discards unsynced offline work on this device; the previous account’s cloud data remains unchanged.

Backup & restore

Portable files you control.

A full backup includes streams, subjects, topics, review history, theme, and exam dates. Restoring replaces the current device data after confirmation. Cloud sync runs automatically while signed in.

Data storage: data is saved in this browser on this device. It does not automatically sync between devices or browsers. Download backups periodically.

Settings

Manage exams, deadlines, and appearance preferences.

Exams & deadlines

Add as many exam dates as you need.

Appearance

Choose the interface theme.

Theme preference is saved in this browser.

Review schedule

The schedule adjusts to each rating and the topic's previous interval.

1 — Again
Repeat in 1 day; interval resets.
2 — Hard
Repeat sooner; roughly 1.25× the prior interval.
3 — Good
Roughly 2× the prior interval.
4 — Very good
Roughly 2.5× the prior interval.
5 — Easy
Roughly 3× the prior interval.
Maximum interval
Intervals are capped at 120 days. This is a simple scheduler, not FSRS.

Reset local data

Deletes topics, exams, settings, and review history from this browser.

Study Hub

Plan study time, find weak areas, track papers, manage mistakes, and measure progress.

Review topic

Choose a date to override the suggested interval. Leave blank to use the automatic schedule.

How well did you recall it without looking?

Choose a rating to preview the next due date.

Add topic

A topic can belong to any stream and subject.

Add stream / course

Streams can represent school streams, university courses, certifications, or personal collections.

Add subject

Subject names can be in any language.

Add exam or deadline

Use this for any examination, test, assessment, or deadline.

Install Nexus

Choose how you want to install the app on this device.

If no install prompt appears, open your browser menu and choose “Install app” or “Add to Home screen” where available. Your study data remains on this device unless you enable cloud sync.

How to use Nexus

Feature guide and data-handling details.

1. Overview

Overview summarises active topics, topics due today, overdue topics, reviews completed today, progress by subject, and the nearest upcoming exam or deadline. “Start review” opens the next due topic.

2. Topics and spaced repetition

Use Add topic to create a lesson. Choose a stream and subject, enter the name, and add optional notes. Use the search box and filters to find topics by name, stream, subject, or due status. Edit an existing topic to rename it or move it. Delete removes the topic from the tracker but its older history entries remain.

Open Review after attempting to recall the material without looking. Choose a recall rating from 1 to 5 and optionally set a custom next review date. Check the preview, then tap Mark as reviewed to save the review. The next due date is based on the review date, rating, and previous interval unless you choose a custom date. Rating 1 resets to one day; higher ratings progressively increase the interval. The maximum interval is 120 days.

3. Streams and subjects

In Setup & data, add streams or courses, then add subjects to each stream. You can use any language and any subject. The starter Commerce stream includes Sinhala Business Studies, Accounting, and Economics lesson names; you can edit these or add another study area.

4. Exams and deadlines

Add any number of upcoming exams, assessments, or deadlines. The overview highlights the nearest future date. Past exams remain listed so you can retain a record; edit or delete entries when required.

5. Review history

Every rating adds a history record with a date, topic/subject snapshot, rating, interval, due date, and optional note. Search or filter the log and export it to CSV. Deleting history does not change the current topic schedule.

6. Backup and restore

Download backup (JSON) exports all app data. Keep a copy outside the browser. Restore validates a backup and replaces the current local data after confirmation. CSV exports are intended for spreadsheet review and are not full backups. Importing an older tracker backup is supported where its data format can be recognised.

7. Theme and installation

The theme button cycles through device setting, light, and dark. On a supported browser, choose Install to add Nexus to your home screen or desktop. If installation is not offered by the browser, open the browser menu and choose “Install app” or “Add to Home Screen” where available.

8. Study Hub

Study Hub adds a budget-based daily plan, estimated topic mastery and weakness detection, configurable expected syllabus counts, a due calendar, an FSRS-inspired optional schedule heuristic, focus-session time logging, practice-paper records, a mistake journal, goals, analytics, bulk topic actions, CSV topic import, and expanded backups. Notifications run only while the app is open and permission is granted; closed-browser reminders require extra push infrastructure.

9. Privacy, storage, and limitations

Your data stays in the current browser's local storage unless you export it. It is not automatically synced to other devices, and clearing browser data can remove it. Use backups when changing devices. Do not treat a browser copy as your only record. The app can be installed and used offline after it has first been opened from a secure hosted address; offline changes remain on that device until you export them.
Saved.
IMPORTANT · DATA CHOICE

What should happen to your offline data?

You have study data on this device. Choose how to handle it for the signed-in account before syncing starts.

Merge offline data

Combine this device’s study data with the signed-in account’s cloud data. Matching records use the offline copy, so review the result afterward.

Use cloud data on this device

Replace the study data on this device with the signed-in account’s cloud backup. Any unsynced offline changes on this device will be discarded.

Replace cloud data with offline data

Upload this device’s study data and overwrite the signed-in account’s existing cloud copy. The cloud version may be lost; choose only if this device has the version you want to keep.

Your choice takes effect before syncing begins. If unsure, choose Merge. Downloaded JSON backups remain untouched.
FOCUS SESSION
00:00
Ready when you are

Deep work, one thing at a time.

Session target · —Saved locally · works offline

Keep this window open while you study. Stop the session to return to the rest of Nexus.

PLAN AHEAD

Review calendar

Upcoming reviews and exam dates, at a glance.

Reviews due Exam