The study is a randomised, within-participants cross-over design trial including 60 patients with rheumatoid arthritis (RA) (20), psoriatic arthritis (PsA) (20) and axial spondyloarthritis (SpA) (20) from the Rheumatology outpatient clinic at Aalborg University Hospital. The participants will be randomised in ratio 1:1 to:
* Group AT (App → Touch) (30 participants) the participant reports data through the DANBIO app on a smartphone first and after a "washout period" of one day via the touch screen solution at the rheumatology outpatient clinic.
* Group TA (Touch → App) (30 participants): the participant reports data through the touch screen solution at the rheumatology outpatient clinic and after a "washout period" of one day via the DANBIO app on a smartphone.
The primary objective is to evaluate whether electronic reporting of PROM through the DANBIO smartphone app is comparable to the traditional touch screen solution in the rheumatology outpatient clinic among patients with inflammatory arthritis in standard clinical care. The primary outcome is HAQ. Secondary outcomes are: VAS pain, VAS fatigue, VAS global Health, BASDAI, BASFI, PASS, Anchoring question, DAS28crp and ASDAS. DAS28crp are estimated using a fixed level for C-reactive protein (CRP) level of 6, swollen joint count of 0.5 and tender joint count of 1. ASDAS are estimated using a fixed level for CRP of 6. These data are based on DANBIO registrations of patients with RA, PsA or SpA from the rheumatology outpatient clinic at Aalborg University Hospital. DAS28crp and ASDAS are estimated from the PROM data to give the clinician an overview of PROM correlating to e.g. remission or high disease activity.