SensorSynthFM Current Build

What Works on the iPad

The accepted July 22 build passed 22 automated Xcode tests and a generic iOS build, then signed, installed, launched, and ran on my 11-inch iPad Pro. When the seven-day development signing profile later expired, a fresh Xcode run signed and installed the same build and it launched again. That interruption was a signing failure, not a product-code failure, and it is worth naming because build history should distinguish the two.

On August 3 I ran an eight-step cognitive walkthrough on the physical iPad, testing the instrument the way a first-time user would encounter it. Seven steps passed:

• Play was visible.
• Sound started, and the playing state made sense.
• The active source and FM destination were clear.
• Manual control and sensor modulation were distinguishable from each other.
• Microphone response was visible and audible.
• Setting a route to zero neutralized it, and restoring the amount resumed modulation.
• I could explain the premise of the instrument in one sentence.

The sensor mappings themselves earned their place through direct testing. Accelerometer magnitude routed to modulation index at +40 percent produced a clear change when the device moved; table taps and stationary vibration did not produce a useful result, which sets a real boundary on what the mapping is for. Gyroscope Y routed to modulator ratio at +41 percent changed timbre and apparent pitch predictably under slow tilting. Microphone amplitude routed to amplitude at +63 percent behaved the way an instrument source should: a quiet tone stayed stable, speech raised loudness proportionally, and claps produced louder transients with a slight apparent delay. That source is worth keeping if it is programmed and limited carefully.

There is also a handedness switch that moves auxiliary controls for left- and right-handed use. It works mechanically. It has not been tested with left-handed users, so I make no claim beyond the mechanism.

What Changed Because It Failed

Every major decision in this build traces to a physical failure, not to a preference. Earlier rounds on hardware produced their own corrections. System chrome, meaning the iPad status area and gesture regions that surround the application, covered controls in an early layout. The first route editor collided with the iPadOS bottom gesture zone. Microphone behavior was too subtle to trust. Fixed routing hid the range of the instrument. Sensor writes made manual controls look broken. A side panel made the primary amount control too narrow, and the native layout hid the ninth source entirely. Each of those failures forced a design change that survives in the current build.

The August 3 walkthrough adds a new required list:

• Selected zero routes stay visibly selected.
• The interface explains that moving the amount activates a route.
• Every active route gets a visible X or remove control. Double-tap may remain a shortcut, but it cannot be the only removal method.
• Sensor response is shown clearly, so the ear and the eye agree.
• All nine sources fit on screen without shrinking touch targets.

What does not change: familiar synthesis controls, bipolar amounts, a visible zero state, large touch targets, and clear source-to-destination routes. Those are the parts the walkthrough validated, and they hold.

The Next Field Pass

The next outside research idea is a visit to an Apple Store to study how users naturally approach and use display iPads. The questions are basic and directly relevant to this instrument: portrait versus landscape, where the first touch lands, one-hand versus two-hand use, reach, grip changes, keyboard and stand use, and how users recover from confusion. An instrument that lives on a tablet should be shaped by how users actually hold tablets, not by how I hold mine.

The first visit is only to understand the setting. Before any formal observation, I will settle the research boundary and obtain any required store permission. I will not record names, demographics, photos, audio, video, or quotes, and I will not interrupt anyone. That is the limit of what is planned.