Inclusion Criteria:

• * Follows at University of Rochester Medical Center Pulmonary Hypertension Clinic.
• * Adult patients (\>18 years old) with right heart catheterization confirmed pulmonary hypertension (PAH) on stable vasodilator dosing for at least 30 days. No planned titrations will occur during the 12-week study. If during the study, the treating physician feels it is necessary for safety reasons to adjust dosing, the subject will remain in their assigned group.
• * Access to a smart phone or email to receive daily messages. If patients do not have access to either, we will offer a smartphone with cellular service for use during the study to receive daily messages.
• * Clinically stable by the investigator (i.e., we will not enroll patients who endorse ongoing improvement or clinical worsening at enrollment).
• * The treating investigator (Dr. Lachant or Dr. White) will review the clinical data of an eligible patient and establish them as safe to participate prior to approaching the patient for enrollment (i.e. not in decompensated heart failure or with recurrent pre-syncopal episodes prior to enrollment).

Exclusion Criteria:

• * Pregnancy.
• * Pulmonary Hypertension Groups 2-5.
• * Resting tachycardia \>120 beats/m during screening.
• * Inability to walk.
• * WHO Functional Class IV
• * Lack of access to email or text messaging.
• * Inability to follow daily instructions. including the two home 6-minute walk tests during the initial monitoring period. This is to show compliance with the protocol.
• * Participating in a self-reported rehabilitation or exercise program.
• * Oxygen therapy of more than 6 L/min at rest.
• * Principal Investigator discretion