The proposed study is a pilot randomized clinical trial (RCT). Participants in the intervention arm will participate in a 90-day adherence promotion program based on the theory of behavioral economics and administered through the Wellth mobile phone application. Subjects will be provided a CleverCap® Lite BLE C035 smart pill bottle (electronic monitoring (EM), device) containing a 90-day supply of aspirin (90 pills) and those in the intervention arm will be offered $150 for app-based medication check-ins, which consist of uploading daily photos of pills at the time of administration through the Wellth app. Subjects will have $2 deducted from total rewards for each day that a medication check-in is missed. Subjects in the control arm will receive usual care and be monitored with the same EM device types used in the intervention arm.

Medication adherence is a quantifiable parameter detailing when and how consistently doses are taken. Elements of medication adherence include: 1) the proportion of prescribed drug taken or %PDT (primary outcome); 2) the proportion of days with the correct number of doses taken; 3) the proportion of doses taken on time, in relation to a prescription-defined time interval between successive doses; 4) the distribution of inter-dose intervals; 5) the number of drug holidays; and 6) the longest interval between two doses [Vrijens et al. British journal of clinical pharmacology. 2012;73(5):691-705]. Medication adherence will be assessed in all participants using EM technology manufactured by CleverCaps®. Electronic Monitoring (EM) is more sensitive, reliable and valid than other measurement techniques such as pill counts, self-reports, or clinical judgment [Vrijens et al. Expert review of clinical pharmacology. 2014;7(5):633-644]. In this study the investigators will monitor a single drug, aspirin, in MI patients prescribed aspirin on hospital discharge.

In addition to measurement of medication adherence using an EM device, the investigators will measure adherence using the Wellth cell phone app in the intervention arm. Participants in the intervention arm will also be asked to track their medication-taking habits by uploading photos of their medications at the appropriate dosage times using the Wellth app.

Readmissions will be measured using the EMR and by interview to capture events outside the Penn system. Events will be classified according to timing (e.g. 30-day readmission) and cause (e.g. cardiac, all-cause). This study is not designed to detect a statistically significant difference in readmissions.

Inclusion Criteria:

• Over 21 years of age
• Admitted to one of the University of Pennsylvania hospitals for acute myocardial infarction (ICD-10 codes I21.xx) or unstable angina (ICD 10 codes I20.xxx)
• Prescribed once-per-day aspirin at discharge
• The patient administers his or her own medications
• Own a smartphone with a sufficient data plan or home Wi-Fi to enable app use and avoid overage charges
• Able to speak and understand English

Exclusion Criteria:

• Diagnosis of MI following non-cardiac admission
• Discharge to any facility other than the patient's home
• Cognitive impairment that limits ability to understand and complete questionnaires
• Inability to operate a mobile phone and the Wellth app
• Physician-estimated life expectancy less than 6 months