This filter screws into the lens. 

Thanks for your question. The monitoring data of the past two years will be stored on the APP. ""Day"" in the graph will display the average value of the data monitored by the detector every hour in the last 24 hours. ""Month"" in the graph will display the average value of the data monitored by the detector every day in the past 30 days. ""Year"" in the graph will show the average value of the data monitored by the detector in each month in the past two years. You can also export the data you need directly through the APP. 

The front lens of the lens is strongly curved and has a permanently integrated lens hood, threads for screwing are not available on the optics. The cap is placed over the lens hood and held in place by latches. I don't see any options for attaching a filter, and I'm not aware of any factory solutions or products from other manufacturers. 

Yes it can. The lens would have to go in the main part of the bag if you are putting a camera in the bottom. But plenty of room for the lens and clothes. 

The Answer is Yes. You can use a pinch cap over most filters. ALL my lenses have a filter of some sort on them. I use to use a lot of "traditional" lens caps on all my old Nikkor lenses but putting them on and taking them off became a giant PITA, so I got a Pinch Cap as a test. I then converted ALL the lenses to Pinch Caps. Hope this helps.