This paper presents the results of a study about the performance and, consequently, challenges of using
smartphones as data gatherers in mobile sensing campaigns to environmental monitoring.
It is shown that there are currently a very large number of devices technologically enabled for tech-sensing
with minimal interference of the users. On other hand, the newest devices seem to broke the sensor diversity trend, therefore making the approach of environmental sensing in the ubiquitous computing scope using smartphones sensors a more difficult task.
This paper also reports on an experiment, emulating different common scenarios, to evaluate if the
performance of environmental sensor-rich smartphones readings obtained in daily situations are reliable
enough to enable useful collaborative sensing. The results obtained are promising for temperature
measurements only when the smartphone is not being handled because the typical use of the device pollutes the measurements due to heat transfer and other hardware aspects. Also, we have found indicators of data quality issues on humidity sensors embedded in smartphones. The reported study can be useful as initial information about the behaviour of smartphones inner sensors for future crowdsensing application developers.