Where Do I Put My Stylus ?

Lost. Again.

Why is there still no place for iPhone users to store their stylus?

Your stylus deserves better. So I designed a solution:

PenKeep: a case that keeps your stylus exactly where it belongs - securely attached to your phone, always within reach.

Product
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Challenge

Steve Jobs famously dismissed the stylus during his 2007 iPhone keynote, saying, "You have to get 'em, put 'em away. You lose them. Yuck!" But as someone who frequently jots down ideas and sketches on my phone, I’ve realized that my oversized fingers just don’t cut it when precision is required.

To Jobs’ point, the biggest challenge with styluses is that they’re easy to lose and inconvenient to carry—there’s often no dedicated place to store them. While brands like Samsung (Galaxy S23 Ultra) and Motorola (Moto G Stylus 5G) have embraced the value of built-in styluses, Apple has yet to follow suit. The Apple Pencil remains exclusive to the iPad, and neither the iPhone nor its accessories offer a seamless way to store a stylus.

Most phone cases lack an integrated holder, leaving stylus users, like me, frustrated. I set out to change that. My goal was to design a sleek, functional, and minimalist case that securely holds a stylus without adding bulk—a smart solution for creatives on the go.

Market & User Research

User Pain Points

To validate this issue, I turned to one of my favorite places for honest, unfiltered user research - Reddit. A quick search confirmed that I wasn’t alone, with many iPhone users posting about the exact same issue:

User Challenges & Preferences
  • 🎨 Desire for Precision & Creativity: Users want to sketch, take notes, and navigate with a stylus for fine control, without relying on their fingers
  • 📱 Portability Over iPads: Many don’t want to carry an iPad just to use a stylus but still want the same precision and convenience
  • 🎒 No Good Storage Solution: With no built-in holder or case support, users end up losing, forgetting, or damaging their stylus
  • Disruptive Workflow: Without a secure place for a stylus, users waste time searching for it or carrying extra accessorie

Based on this, I developed the following product requirements:

User Stories (Product Requirements)

As a user who frequently misplaces my stylus, I want a phone case with a dedicated stylus holder, so that I can keep my stylus attached to my phone and never lose it.

As a creative who draws & takes notes on my phone, I want a case that makes my stylus easy to access, so that I can easily remove my stylus to jot down ideas without carrying extra accessories 

As a user who values aesthetic appeal and convenience, I want the stylus holder to be sleek and low-profile, so that my phone remains portable and comfortable to hold in my hands

As a user concerned about durability, I want a case that protects both my phone and stylus, so that I don’t have to worry about damage from drops or scratches, prolonging product use

As someone who uses different styluses, I want the case to fit multiple stylus sizes, so that I can choose the stylus that works best for me and have the ability to easily replace a stylus

Target Audience

✔ Creative Professionals – Designers, architects, and artists who use styluses for precision tasks

✔ Students & Note-Takers – Users who rely on styluses for quick annotations and studying

✔ Business Professionals – Executives and professionals who use styluses for signing documents and productivity

✔ Everyday iPhone Users – People who prefer styluses for better control but struggle with carrying them conveniently

Competitive Landscape

Currently, there are limited solutions available for iPhone users looking for stylus storage. The existing alternatives include:

Adhesive Stylus Holder

Small adhesive pockets that attach to the back of a phone

Cases with Built-In Mini Styluses

Some phone cases include a mini stylus as part of the design.

Phones with Built-In Styluses

Devices like the Samsung Galaxy S23 Ultra that have integrated styluses within the phone itself.

✅ Pros: No need to buy a new case

❌ Cons: Adhesive weakens over time, leading to detachment; adds bulk to the back.

✅ Pros: Stylus remains attached to the case

❌ Cons: Mini styluses are uncomfortable for extended use, and users must use the included stylus instead of their preferred one.

✅ Pros: Stylus is securely stored inside the phone

❌ Cons: This feature is exclusive to certain phone models, leaving iPhone users without a solution.

Value Proposition of PenKeep Case

Compared to the limited alternatives available, PenKeep stands out as a versatile, integrated solution that allows users to bring their own stylus while accommodating a variety of types. Unlike add-on attachments, PenKeep is seamlessly built into the phone case, ensuring greater durability and ease of use.

Prototyping & Design Considerations

Before moving into 3D modeling and printing, I identified several key design challenges that influenced the final prototype. These considerations ensured that the case would be both functional and user-friendly while working within technical constraints.

Physical Constraints:
Where Can the Stylus Go?
  • Port Accessibility: iPhones have ports on three sides (bottom, left, and right), making the top the only viable location for a stylus holder without blocking key functionalities

  • MagSafe Charging: Newer iPhone models use magnetic charging on the back, meaning any permanent stylus storage there could interfere with charging and accessories

  • Ergonomics: The case must allow for comfortable grip and usability—a holder that’s too horizontal or vertical could make holding the phone awkward.
Material & Manufacturing
Constraints
  • 3D Printing with PLA: Since the prototype will be 3D printed in PLA, the case will be rigid rather than flexible, unlike traditional TPU or silicone cases. This impacts:
    • The grip and feel of the case
    • The durability and shock absorption compared to commercial cases

  • Future Iterations: While PLA is suitable for prototyping, a future version could incorporate flexible TPU for a more comfortable user experience.
Stylus Compatibility:
One Size Doesn’t Fit All
  • Stylus Variability: Users may have different stylus lengths, thicknesses, and brands (e.g., Apple Pencil, Adonit, generic capacitive styluses)

  • Adjustable Design: The holder needs to:
    • Secure different stylus sizes without being too tight or too loose
    • Allow for easy insertion and removal without excessive force
    • Maintain a (relatively) sleek profile to avoid unnecessary bulk.

Design Process

Prototype #1: Initial Testing

For my first iteration, I designed a built-in stylus holder within the phone case. However, I encountered two major issues:

1. Added Bulk – The integrated holder significantly increased the overall size of the case, making it less sleek

2. Length Limitation – The holder could only be as long as the phone itself, meaning longer styluses wouldn’t fit properly, limiting compatibility.

Prototype #2: Sleeker Design

To address bulkiness, I redesigned the case with the stylus holder positioned on top—the only location that met usability requirements while maintaining a slimmer profile. However, new challenges emerged:

Stylus Fit Issues – The holder worked well for larger styluses, but smaller ones fell out easily due to the oversized slot

Printing Challenges – When printing with the front face down, the uneven connection between the stylus holder and the case required supports, leading to an imperfect surface.

🔹 Key Fix: Future iterations need uniform base height to ensure smooth 3D printing and adjustable grip for different stylus sizes.

Prototype #3: Adjustable Holder

This iteration focused on creating a versatile holder that could accommodate various stylus sizes. Key considerations included:

✔ Flexible grip mechanism to securely hold different stylus widths.

✔ Refined attachment design to prevent stylus slippage while maintaining a minimalist form.


This iteration moved closer to a functional, adaptable solution (using threads to hold the stylus in place) that could work across multiple stylus brands and sizes.

Final Solution/Prototype

Product Demo

Love what you see?

Please feel free to reach out!

linkedin.com/in/dagoye
deborahagoye@gmail.com