User Manual

Getting Started

Everything you need to know to set up and use your Nexus Pen — from unboxing to your first AI conversation.

01

What's in the Box

  • Nexus Pen Donna (AI-powered smart pen)
  • USB-C charging cable (1m)
  • Ink cartridge (pre-installed)
  • Spare ink cartridge × 1
  • Quick Start card
  • Premium magnetic gift box

Missing an item? Contact NexuspenLLC@gmail.com within 14 days of delivery and we'll make it right.

02

Charging Your Pen

  1. Locate the USB-C port at the base of the pen cap.
  2. Connect the included USB-C cable to the pen and a USB power adapter (5V/1A minimum).
  3. The OLED display will show a charging animation while power is connected.
  4. A full charge takes approximately 60–90 minutes. The display reads "FULL" when complete.
  5. Disconnect and replace the cap. Your pen is ready to use.
  • Battery life: Up to 6 hours of active use, 72 hours standby
  • Battery indicator: Top-right corner of OLED shows bars (full, medium, low, critical)
  • Low battery warning: OLED flashes "LOW BAT" when under 10%
03

Download the App

The Nexus Pen app handles pairing, AI mode selection, conversation history, and account management.

Download on the App Store
Get it on Google Play

Requires iOS 15+ or Android 8.0+. A free account is required. Sign up at nexuspen.org or inside the app.

04

Pairing via Bluetooth

  1. Power on the pen by holding Button A (top button) for 2 seconds. The OLED will show "NEXUS PEN".
  2. Open the Nexus Pen app on your phone and sign in to your account.
  3. Tap "Connect Pen" on the home screen. The app will scan for nearby devices.
  4. Select "Nexus Pen Donna" from the device list.
  5. The pen OLED will display "PAIRED" and a brief confirmation tone will play.
  6. The app home screen will show a green connection indicator and battery level.

The pen remembers the last paired device and reconnects automatically when both Bluetooth and the app are active. You do not need to re-pair each time.

05

Your First Question

  1. Make sure your pen is paired and connected (green dot in app).
  2. Hold the PTT button (Button A) down and speak your question clearly into the pen's microphone at the top.
  3. Release the button when you finish speaking. The OLED shows "THINKING..."
  4. Within 1–3 seconds, Donna's voice response plays through the pen's built-in speaker.
  5. The OLED displays a short summary of the response while audio plays.
  • Button A (top): Push-to-talk (hold to record, release to send)
  • Button B (middle): Cycle AI mode
  • Button C (bottom): Open settings menu on OLED
06

AI Modes Explained

Press Button B to cycle modes. The current mode is shown on the OLED. Modes shape how Donna responds — same question, different approach.

Answer Now

Default Mode

Fast, direct answers. No fluff. Great for quick facts, definitions, and on-the-go questions.

"What's the capital of France?" → "Paris."

School

Educational

Explains concepts step by step — like a patient tutor. Breaks down complex topics for real understanding.

"Explain photosynthesis" → full breakdown with steps

Research

Deep Dive

Thorough, detailed responses with nuance. Best for essays, reports, and when you need depth.

"Causes of World War I" → structured deep analysis

Creative

Imagination

Writes stories, poems, brainstorms ideas, and thinks outside the box. Great for creative projects.

"Write a short poem about space" → original poem

Language

Translation & Grammar

Translates text, corrects grammar, explains idioms, and helps with foreign language learning.

"How do you say 'good morning' in Japanese?"

Pro users can create a custom mode with a personalized system prompt — set it up in the app under Settings → Custom Mode.

07

OLED Display Guide

Screen Text / Icon What It Means
NEXUS PENBoot screen — pen is starting up
READYConnected and waiting for your question
LISTENING...PTT button held — recording your voice
THINKING...Sending to AI, waiting for response
PLAYINGAudio response is playing through speaker
Mode: ANSWERCurrent AI mode displayed after mode change
Vol: 75%Volume level shown after adjustment
LOW BATBattery below 10% — charge soon
FULLBattery fully charged
NO CONNBluetooth not connected to app
ERRORRequest failed — check connection and retry
Battery bars (top-right)Real-time battery level indicator
08

Voice Commands

Say these commands while holding the PTT button. Donna detects them and executes instantly — no AI response needed.

"Donna mute"
Sets volume to 0% — pen remains active but silent
"Donna max volume"
Sets volume to 100%
"Donna lower volume"
Decreases volume by 20%
"Donna raise volume"
Increases volume by 20%

Volume changes are saved to the pen's memory (NVS) and persist after power-off. You can also adjust volume in the app under Settings.

09

Settings & Customization

  • Volume — Adjust in-app (Settings → Pen Volume) or use voice commands. Range: 0–100%. Saved on pen.
  • Default AI Mode — Set your preferred startup mode in the app. Pen always boots into this mode.
  • Display Brightness — Hold Button C to open the on-pen settings menu, then use Button A/B to adjust OLED brightness.
  • History Retention — Choose how many days of conversation history to store in the app (7, 30, 90 days, or forever).
  • Custom Mode (Pro only) — Write a custom AI personality prompt. Set in app under Settings → Custom Mode.
  • Account & Subscription — Manage plan, password, and billing in-app under Account or at nexuspen.org.
10

Troubleshooting

Bluetooth won't connect / pen not found in app
  1. Make sure the pen is powered on (OLED shows "NEXUS PEN" or "READY").
  2. Close and reopen the Nexus Pen app.
  3. Toggle Bluetooth off and on in your phone's Settings.
  4. Ensure no other phone is already connected to the pen — the pen only supports one connection at a time.
  5. Move within 3 metres of the pen and try again.
  6. If still failing: hold Button A + Button C together for 5 seconds to reset BLE state. The OLED will show "BLE RESET".
No audio / very quiet sound
  1. Check volume with a voice command: say "Donna max volume" while holding PTT.
  2. Verify volume is not set to 0% in the app (Settings → Pen Volume).
  3. Make sure the speaker grille (near Button C) is not covered or blocked.
  4. Try a different AI response — short responses may be very brief.
  5. Restart the pen (hold Button A for 5 seconds until OLED turns off, then power on again).
Pen won't turn on
  1. Connect the pen to USB-C power. Wait 60 seconds — a fully depleted battery may need time before the OLED activates.
  2. Try a different USB cable or power adapter.
  3. Charge for at least 15 minutes before attempting to power on.
  4. If still unresponsive after charging, contact NexuspenLLC@gmail.com — this may be a hardware issue covered under warranty.
OLED shows "ERROR" or "NO CONN"
  1. NO CONN means the pen is not paired to a phone with the app open. Open the app and reconnect.
  2. ERROR means a request failed — check your internet connection on your phone.
  3. Force-close and reopen the app, then reconnect the pen.
  4. If the error persists, check status at nexuspen.org/help.
How to factory reset the pen

A factory reset clears all saved settings (volume, mode, paired devices) and returns the pen to default state.

  1. Hold Button A + Button B + Button C simultaneously for 8 seconds.
  2. The OLED will display "RESETTING..." then reboot.
  3. Re-pair to the app and reconfigure your settings.

Note: This does not delete your account or conversation history in the app.

Still stuck? Email NexuspenLLC@gmail.com with your order number and a description of the issue. We typically respond within 24 hours.