The investigators will send participants supportive text-messages for a period of 2 months. These text-messages will include tips about behavioral activation and coping skills to deal with worries and stress. The investigators generated a message bank balanced such that 50% of all messages are related to behavioral activation (BA) and 50% messages involve different coping skills. Participants will receive one of these messages per day between 9:00 am and 6:00 pm. Participants will also receive a message asking them to rate their mood on a scale of 1-9 once a day 3 hours after the BA or coping message.~Participants will be randomized to:~a uniform random messaging group (micro-randomized trial design).~a reinforcement learning group with a learned decision mechanism for the timing and type of text-message. The algorithm learns from previous data (which messages were sent, what was the participants' mood) to maximize an increase in participants mood. No other data are collected from participants' phones.~The investigators will compare the effect of sending text-messages by a random schedule, and text-messaging chosen by the RL algorithm. This allows to both evaluate the effect of the individual intervention components over time within a micro-randomized trial design, and assess the added value of using RL to adapt the messaging scheme.~The investigators hypothesize that:~Participant will show improvements in depression, anxiety symptoms and mood during the 60 day study.~The participants in the group receiving reinforcement learning will have a greater improvement in depressive symptoms, anxiety and positive mood during the study than participants in the micro-randomized group.~The investigators will find differential effects on mood ratings for the two categories of messages
The investigators have developed supportive text-messages in English and Spanish to help people cope with the stress and anxiety of COVID-19 social distancing. The purpose of this study is to examine if automated text-messages will improve depression and anxiety symptoms and enhance positive mood.~Additionally, the investigators will compare the effectiveness of sending messages on a random schedule (using a micro-randomized trial design) or sent by a reinforcement learning policy on overall change in depression and anxiety symptoms and daily mood during the 8-week study.