Imagine a scenario when all mobile phone companies finally decided to add a custom default bitcoin wallet to all of their devices as factory app. I believe that will further increase the adoption of bitcoin
Wack, all surveillance agencies would welcome this. Default bitcoin wallet on mobile threatens you privacy because of gyro sensor on the board of cell phone. The data from that sensor can be easily lifted, so surveillance agencies use it to their advantage to build the fingerprint of your walking manner. If you care the privacy of your transactions don't keep bitcoin (and any crypto) on mobile.
Yeah, privacy inference attacks based on accelerometer and gyroscope sensor data are a new and dangerous threat to smart devices. Some mobile platforms, like Android, have no restrictions on the use of these sensors. Also, many companies and manufacturers tend to forget about the privacy issues when making a design decision for their devices. It seems that we are now entering a new era where privacy is not a big priority for companies in this field.